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BAK Industries

BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish

148 Reviews | 18 Questions

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$1,249.99

Retail:$1,321.88

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1 used item available at $1047.94

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2000 Ford Excursion

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Product Images

bak industries tonneau cover fold-up - hard tailgate lock bak448133

bak industries tonneau cover fold-up - hard aluminum

bak industries tonneau cover tailgate lock aluminum bak448133

bak industries tonneau cover fold-up - hard tailgate lock bakflip mx4 folding aluminum matte finish

bak industries tonneau cover fold-up - hard aluminum bakflip mx4 folding matte finish

bak industries tonneau cover fold-up - hard

bak industries tonneau cover tailgate lock bak448133

bak industries tonneau cover fold-up - hard bakflip mx4 folding aluminum matte finish

bak industries tonneau cover tailgate lock

bak industries tonneau cover aluminum bak448133

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In Use/Installed

2016 gmc sierra 1500 tonneau cover bak industries fold-up - hard aluminum bakflip mx4 folding matte finish

2016 gmc sierra 1500 tonneau cover bak industries aluminum bak448133

2016 gmc sierra 1500 tonneau cover bak industries tailgate lock on a vehicle

2016 gmc sierra 1500 tonneau cover bak industries tailgate lock aluminum bak448133

2016 gmc sierra 1500 tonneau cover bak industries fold-up - hard tailgate lock bak448133

2016 gmc sierra 1500 tonneau cover bak industries fold-up - hard aluminum on a vehicle

2016 gmc sierra 1500 tonneau cover bak industries tailgate lock bak448133

2016 gmc sierra 1500 tonneau cover bak industries fold-up - hard on a vehicle

2016 gmc sierra 1500 tonneau cover bak industries fold-up - hard tailgate lock bakflip mx4 folding aluminum matte finish

2016 gmc sierra 1500 tonneau cover bak industries fold-up - hard bakflip mx4 folding aluminum matte finish

0 tonneau cover bak industries aluminum bak448133

0 tonneau cover bak industries fold-up - hard aluminum on a vehicle

0 tonneau cover bak industries tailgate lock bak448133

0 tonneau cover bak industries fold-up - hard tailgate lock bakflip mx4 folding aluminum matte finish

0 tonneau cover bak industries tailgate lock on a vehicle

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Videos

BAKFlip MX4 Hard Tonneau Cover 30 Second Overview

BAKFlip MX4 Hard Tonneau Cover In-Depth Review and Installation

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Get style and versatility with this heavy-duty, all-aluminum tonneau. Quad-fold cover sits inside your vehicle's bed rails and secures upright for unrestricted bed access. Tailgate opens and closes with cover up or down. Matte black finish. Great Prices for the best tonneau cover from BAK Industries. BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish part number BAK448133 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.

BAK Industries Tonneau Cover

Features:

Custom-fit tonneau cover protects your cargo and your vehicle's bed from the elements
- Aerodynamic style reduces wind drag, improving gas mileage
Quad-fold design allows for partial or full truck bed access in seconds without having to remove cover
- Prop rods let you secure folded cover in upright position so you can drive with truck bed completely open
- Integrated buckle system lets you secure the cover in the folded, flipped up, or closed position
Low-profile cover sits inside your truck bed rails
- Compatible with stake-pocket-mounted accessories and raised side rails
Automatically latching panels create a secure truck bed when tailgate is closed and locked
- Rear seal lets you open and close tailgate with cover open or closed
Matte black rubber seals and built-in drainage system help to keep water out of bed
1/2" Thick, rustproof aluminum panels are sturdy and durable
- Premium density foam core adds strength
- Cover rated to hold up to 400 lbs of evenly distributed weight
Matte black finish is resistant to scratches, scuffs, and UV rays
Aircraft-grade, rustproof aluminum rails with black powder coat finish create base for tonneau
Easy, no-drill installation
- Frame rails clamp to the inside of your truck bed side rails
- Included bolts secure front hinge rail to frame rails
Compatible with BakBox2 (sold separately)
Made in the USA
5-Year warranty

448133 BAK Industries BAK Flip MX4 Hard Folding Truck Bed Cover

Item # BAK448133

Installation Details BAK448133 Installation instructions

This Product Fits The Following Vehicles

2020 - 2028 GMC Sierra 2500 6-3/4 Foot Bed
2020 - 2028 GMC Sierra 3500 6-3/4 Foot Bed
2020 - 2028 Chevrolet Silverado 2500 6-3/4 Foot Bed
2020 - 2028 Chevrolet Silverado 3500 6-3/4 Foot Bed

Customer Satisfaction Score:

96% were satisfied with this product

4% of customers were not satisfied

Wrong item was ordered

4% of customers were not satisfied

Wrong item was ordered

4.6

148 reviews

5 Stars		(110)
4 Stars		(24)
3 Stars		(10)
2 Stars		(1)
1 Star		(3)

by: Chris 02/20/2021 One Year Later

Works great and 5th wheel hitch fits underneath and when folded up I can hitch up my trailer without removing cover. Only issue is the corner pieces on the end section came off and I can’t get manufacturer to help me get replacement.

by: Chris 02/28/2021 One Year Later

This cover is great. My only wish is it could fit a little tighter side to side. I've had it 1 year and it has worked and held up perfectly.

by: Donald 04/05/2022 One Year Later

Good quality and relatively easy to install !!
Good value for the money too !!

by: James 08/04/2021 One Year Later

I love it, I’ve owned three

by: Reed 09/19/2023

by: quinn 11/22/2024

by: John B 07/12/2026 One Year Later

I love how this tonneau cover works. because it allows use of almost the entire bed of the truck when it's fully open. I was a little disappointed with the clamps for installing the side rails, as they didn't seem as robust as the clamps in the cover I bought for my last truck. However, I am happy with its operation, and the fact that the truck bed is a locked compartment when I lock the tailgate.

Claire H.

7/14/2026

Thanks for the great feedback! We're glad you're enjoying the tonneau cover and that being able to use almost the entire truck bed when it's open has been such a big plus. It's also nice knowing your gear stays secure when you lock the tailgate. We appreciate you mentioning the clamps too—that kind of feedback is always helpful. Thanks again, and we hope you keep enjoying your new cover!

by: Gordon 05/21/2025

2022 Ford F-350 Super Duty

Bought it used.. I asked if it was complete undamaged.. It arrived complete including a scratch on the inside cover.. I'm glad it wasn't on the outside cover. Shipping was quick. Installation was fairly straight forward

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by: Doug 12/31/2025

Ordered the BAKFlip MX4 for my son on 12/15 after calling to verify the tonneau would arrive by Christmas. Then received an email that said "Your order has been forwarded to one of our partners for direct shipment to you" and never received another shipping update or any tracking info. Finally on 12/22 I emailed Etrailer.com who told me they didn't know when I would get it. The Tonneau finally arrived on 12/29, 3 days after my son returned to California (he drove his truck, 2100 miles). He won't be back till next Christmas so I have to figure out how to return this product. I had several other buying options to get this here by Christmas, but went with Etrailer because of their reputation. This will be my last purchase from Etrailer.com.

by: David 04/10/2022 One Year Later

Overall, I am very pleased with my BAKFlip MX4. It has held up well after 1 year. It works well and looks good. It matches my matte black accessories and trim. It was fairly easy to assemble but I did have some tight fitment issues near the cab where the cover connects to the rail. I really like the security of the hardtop and access through the tailgate. Water is generally kept out, but sometimes there are water drips near the tailgate depending on the angle parked. So this cover keeps the bed *mostly* dry.
etrailer was very fast to deliver my cover, and it came in good condition.

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by: Christopher 12/09/2025 One Year Later

The bed cover has been great so far. Followed the instructions and took my time adjusting it and it has been working well. Keeps the bed dry and looks good. I did have to order an extra kit to get enough rail clamps. Once I put the extra clamps on it feels much more secure. For 8ft beds they need atleast 8 to 10 clamps, not 6. The cover has been working in that I don’t have to uncover the whole bed to use it. I just need to open up as much as I need at the time.

by: Pete 11/14/2025 One Year Later

Pontiac Trans Sport Van

BAKFlip MX4 is a great addition to any pickup. It allows for secure transport of material, keeping it dry in bad weather and yet readily accessible with the flip of a panel. It also keeps the weather away from your 5th wheel hitch. Can be left on when towing.

by: Chris B. 09/26/2020 One Year Later

So after a year I am still loving this bed cover. Had the fiberglass version for my 2013 F-150 and loved it as well, that's why I purchased this one for my 2019 Super Duty, it was also the first accessory I purchased for it because I was so used to my other one and knew I couldn't live without it. I never installed the drain tubes on either covers and still haven't had water get it my bed. Also the folks at etrailer are always awesome! Thanks again!

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by: Justin 04/23/2024 One Year Later

I have been using this cover for almost a year now, and am very pleased with it. It looks and fits great, and it is secure and keeps most of the bed dry in the rain. A couple of rubber trip bits have needed some improved securing, and I used a little RTV so it was easy. I drove it across the country round trip last summer and it was perfect. I would recommend this cover for a great-looking and pretty secure cover. Finally, it is easy to fold forward when it is time to haul loads taller than the bed rails.

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by: Rob 06/02/2024 One Year Later

Purchased this BAKFlip for my new 22 RAM Classic 1500. Installation went well, instructions were good to follow, and it fit perfectly. One of the plastic hold down clips had a manufacturer defect with excess plastic mold residue inside the clip that prevented it from properly working. I sent an online warranty claim explaining the problem, and a new clip was sent to me in a reasonable amount of time, and it worked fine. After one year of using the cover, I am very happy with it. Everything functions as it should, and it is very versatile. While it is not 100% watertight, I mostly notice a small amount of leakage around the tailgate seal after washing the truck. Under normal rainy weather, there is no leakage, and we get plenty of rain in the PNW. My four-star rating rather than a 5 star is only because of the manufacturer defect and the curling of one of the rubber cushions on the underside of one of the panels where the adhesive holding it on the edges has not held up under the hot weather (with the black color, when the sun beats down on the cover it gets pretty toasty inside the truck bed with the cover closed). I am thinking that should be an easy fix by applying some good adhesive and taping in place until the adhesive cures. Just haven't gotten around to doing it. Again, really like this cover. Would recommend it to others, and if I ever have a need for one in the future, would definitely not hesitate getting another BAKflip.

Rob One Year Later

6/4/2025

The BAKFlip after 2 years is still functioning great. I fixed the curling cushion by applying some strong adhesive to the spots that had detached, taped it in place and let cure for a couple of days. That solved that issue. Would continue to recommend the BAKFlip to others.

by: Michael 03/29/2026

Great tonneau cover. Fits as it should.

by: Gene 03/05/2026 One Year Later

dodge Ram Pickup

Great fit on a Ram 2500 long bed. Everything stays dry on the inside.

by: Tianhe 03/26/2018

2017 Dodge Ram Pickup

I installed the BAKFlip MX4 in my RAM 2500 Crewcab has the 6' 1/2 short bed, drived 300 miles now. good product, open and close the tailgate without lifting up the cover

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by: Jason V 02/28/2023 One Year Later

The cover functions ok. The tailgate leaks quite a bit. The manufactured edges that where cut were sharp and not painted or treated. The weather strip along the edges has already discolored/faded. Disappointed in the fading and less than ideal sharp edges. Somewhat expected leaks, but not this much. Average at best rating, especially for the price.

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by: S 08/13/2025

Install was smooth and got a timely note when it was completed

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by: Mike M. 11/21/2020 One Year Later

I am a huge fan of the BAKFlip. The installation was pretty straight forward and easy. Anybody with moderate mechanical ability can install. I think it took less than 2 hours. I live in a heavy snow area and had more than 24” of snow on it at one point and the product performed flawlessly.

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by: Greg 05/23/2026

Excellent product! Wait time was crazy but manufacturer is to blame on that one!

by: Douglas 08/29/2025 One Year Later

I replace a camper shell with the tonneau cover because it is easier to remove when I want to put my pickup camper on the pickup. I am very happy with the cover and am glad I made the switch.

by: Dean 04/21/2021

the bedcover finally came in.
Few pictures of it installed.

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by: Robert 09/05/2025 One Year Later

I own three of these on three different trucks. The two I purchased this year and last year are not as good quality as the one I purchased in 2023.For the price they are feeling pretty cheap now and parts are falling off. Latch covers and rubber par to rest the top on when folded up have fallen off on both of the covers. I will not be buying these brand covers again.

148

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See what our Experts say about this BAK Industries Tonneau Cover

Do you have a question about this Tonneau Cover?

Recommended Folding Tonneau Cover and Truck Bed Bike Rack for 2024 GMC Sierra 2500 Denali Ultimate
Hi Richard; I'm assuming you want a hard folding tonneau cover for your 2024 GMC Sierra 2500 Denali Ultimate. Assuming that is correct, I recommend the BAKFlip MX4. If you have the 6-3/4' bed you need the # BAK448133 and for the 8' bed the # BAK24FR. Then for a truck bed bike rack we have the Saris Traps Fork-Block 3 Bike Rack # SATRK33-BLK3. This sits on the floor so it won't require permanent installation and it won't interfere with the tonneau cover when it is open. We don't have a...
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How Thick is BAKFlip MX4 When Folded on Front Panel
Hey Phil! The BAKFlip MX4 Hard Tonneau Cover # BAK448133 is approximately 3" thick when folded onto the front panel up at the cab of the truck. The panels are 1/2" thick but they don't fold perfectly flat and there is some other material in there as well. If you count where the latches sit it is closer to 4-1/2". Will that work for you? If not, you might want to consider a retractable cover like the Pace Edwards Switchblade # PE63CV.
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Comparing The BAKFlip MX4 And FiberMax HArd Tonneau Covers For A 2024 GMC Sierra 2500
Hey Deen, I've listed out the main differences between the BAKFlip MX4 Hard Tonneau Cover # BAK448133 and BAKFlip FiberMax Hard Tonneau Cover # BAK1126133 below: The MX4 has a matte-black finish whereas the FiberMax has a textured, gloss-black finish. The dual-action tailgate seal on the MX4 allows you to close your tailgate whether the cover is open or shut. The flap seal on the FiberMax overlaps your tailgate, so the tailgate needs to be shut before the cover is closed. The fiberglass...
view full answer...
Tonneau Cover that Fits 2012 Ford F-250 Long Bed with Tool Box Flush with Rails
Hey Sam, since you have a tool box that is flush with your bed rails you would want a tonneau cover that sits on top of those rails so that it would fit with the tool box. For that we have the Extang Trifecta part # EX92725 which is a confirmed fit for your truck. The BAK you mentioned would not work for this purpose.
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Choosing Between Leer and BAK MX4 Tonneau Cover for 2024 Chevrolet Silverado 2500
Hi JD; if I had to choose between the Leer Hard Tonneau Cover # LE67FR and BAKFlip MX4 # BAK448133 I would go with the MX4. As far as security goes both are locking covers so it will be about the same between the two. The MX4 has seals and drain tubes while the Leer only has seals. For the warranty, BAK offers a 5-year warranty compared to a 3-year from Leer. I'm not sure how either of them responds to warranty issues but I can tell you when we have questions about products that require...
view full answer...
Thule TracRac SR Compatibility With BAKFlip MX4 Folding Tonneau Cover
Technically, the Thule TracRac SR Sliding Truck Bed Ladder Rack w/ Cantilever - 1,250 lbs, part # TH44RE, will fit your vehicle with the MX4 tonneau cover. But you will have to shift the uprights of your ladder rack anytime you open your tonneau cover. The overlap of your BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish, part # BAK448133, is not the reason the Thule TracRac SR is not the best fit for your 2022 Chevrolet Silverado 2500. Your tonneau cover is a tri-fold....
view full answer...
Is BAKFlip MX4 or F1 Tonneau Cover Better for 5th Wheel on 2022 Chevy Silverado 3500 Short Bed
While there are minor differences between the two BAKFlip tonneau covers for your 2022 Chevy Silverado 3500 with a 6-1/2 foot bed, for the purposes of using either cover when towing a 5th wheel, there is no real advantage with either the BAKFlip MX4 Hard Tonneau Cover # BAK448133 or BAKFlip F1 Hard Tonneau Cover # BAK772133. The biggest difference between the two is that the F1 has more robust panels, made out of a reinforced polymer (a type of plastic designed for durability) and measuring...
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Do the Truck Hero TS Rais Work with the Gator EFX Covers
Yes the TS Rails for Truck Hero Elevate Rack System part # TH65FR will work out well with your Gator EFX Tonneau Cover. The design of the Gator EFX is very similar to that of the BAKFlip MX4 Hard Tonneau Cover part # BAK448133 which is confirmed to fit with the TS Rails.
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Would BAKFlip MX4 Tonneau Cover Block Third Brake Light Camera of 2024 Chevy Silverado 3500
With the BAKFlip MX4 # BAK448133 installed on your 2024 Chevy Silverado 3500 short bed it would block the third brake light camera when folded up but I do have a solution that would work. Instead you would want to go with a retracting tonneau cover like the part # PE63CV which would give you access to the bed for your gooseneck hitch and allow you to use camera.
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Comparing The BAKFlip F1 And BAKFlip MX4 For The 2020 GMC Sierra 2500 With 6-3/4 Bed
The BAKFlip F1 Hard Tonneau Cover - Folding - Aluminum and Fiberglass # BAK772133 and BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish # BAK448133 are very similar but there are a few minor differences. The F1 has a rough texture that tends to hold up better against various conditions and does not get easily scratched or dented. The MX4 has a smoother appearance and texture and does not have a rough look or feel to it. I think the F1 looks better and it holds up better...
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Recommended Tonneau Cover For a 2024 GMC Sierra 2500 Compatible With Thule TracRac Ladder Rack
I recommend installing the BAKFlip MX4 Hard Tonneau Cover on your 2024 GMC Sierra 2500. You will need either the 6-3/4' # BAK448133 or 8' # BAK24FR cover depending on your bed length. These covers will fit the Thule TracRac which fit the SR rails. If you have a TracRac TracONE # TH27000XT style ladder rack you will need the following components to convert it to fit the SR Rails. Modular Base LF/RR # TA01-42003 Qty 2 Modular Base RF/LR # TA01-42004 Qty 2 Knob # TAKB-90030-1 Qty 4 Nylon...
view full answer...
Ladder Rack Recommendation for a 2023 GMC Sierra 2500 with a BAKFlip MX4 Cover
Technically, yes, the BAKFlip MX4 Hard Tonneau Cover and TracRac SR Ladder Rack (with the Cantilever) will fit together on your 2023 GMC Sierra 2500: - BAKFlip MX4 Hard Tonneau Cover # BAK448133 - Thule TracRac SR # TH94RE - Thule TracRac SR (w/Cantilever) # TH44RE The reason this isn't a definitive "yes" is while the tonneau cover will be able to open (you might have to shift the uprights of the rack to accomplish this), the rubber seals on the sides of the BAKFlip MX4 panels will...
view full answer...
Differences Between BAK BAKFlip G2 and MX4 Hard Folding Tonneau Cover for 2022 GMC Sierra Short Bed
In a nutshell, the MX4 part # BAK448133 is of a slightly higher quality than the # BAK226133 G2. The MX4 has a 5 year warranty versus the 3 year for the G2. The MX4 has a matte finish that does a better job of hiding imperfections and scratches than the gloss finish used on the G2, and the MX4 just feels a bit more substantial as if it'd hold up a bit better over time. Also, the rear seal of MX4 allows you to close the tailgate whether the tonneau is open or not. With the G2, the tonneau...
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What is the Difference Between the BAKFlip G2 and MX4 for 2020 GMC Sierra 3500 Short Bed
The main difference between the G2 # BAK226133 and the MX4 # BAK448133 is that the MX4 can remain latched in position when latching the tailgate. With the G2 the cover must be unlatched to latch the tailgate. This can become kind of a pain if you're leaving the cover in position for an extended period, but constantly at the tailgate. The G2 also has a glossy finish on it, while the MX4 has more of a matte finish and is generally a more sturdy cover when it comes to holding up over time. At...
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Does BAKFlip MX4 Tonneau Cover For 2022 Chevy Silverado 2500 Standard Bed Fit w/ Adarac Ladder Rack
Yes, the BAKFlip MX4 tonneau cover is absolutely compatible with the Adarac Aluminum Series ladder rack on your 2022 Chevy Silverado 2500. The correct part numbers for the cover and rack that fit your truck are the following: - BAKFlip MX4 Hard Tonneau Cover # BAK448133 - Adarac Aluminum Series Custom Truck Bed Ladder Rack - Aluminum Finish # A4003992 or Matte Black # A36HG The MX4 installs inside your Chevy's bad rails, while the Adarac uses the stake pocket mount on top of the bed...
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Rapid Switch Pro On A 2021 GMC Sierra 2500 HD with 610 bed with Bakflip MX4
The BakFlip MX4 is compatible with the Rapid Switch Ladder Rack # RS77FR. These systems work well together and the Rapid Switch System is the same for the 8 foot and 6-3/4 foot bed. For your tonneau cover, it all depends on the length of your bed. If you're wanting to get the BakFlip MX4 and you have a 8 foot bed, get this one # BAK24FR and if you have the 6-3/4 foot bed get this one # BAK448133. The rails are long enough to go from the bulkhead of the bed to the tailgate. I have an installation...
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Rightline Truck Bed Tent Compatibility With A 2022 GMC Sierra 3500 With A BAKFlip MX4 Tonneau Cover
The Rightline Truck Bed Tent # RL110730 attached more to the outside of the bed so you'll have no issues using it on your 2022 GMC Sierra 3500 in conjunction with your BAKFlip MX4 # BAK448133 tonneau cover.
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Adarac Ladder Rack Compatible With The BakFlip Mx4 Tonneau Cover On A 2021 Chevrolet Silverado 2500
If you have the BackFlip MX4 # BAK448133 tonneau cover on your 2021 Chevrolet Silverado 2500 then you can use the Adarac Pro Series Ladder Rack # A4003991. You will need to get this rack because the towers holding the crossbar up is completely upright. These only come in silver. This one comes in black # A4004148 but won't work because of the towers tapering inward. You will most likely have contact with your first panel on your tonneau cover with the tower when you're folding it up.
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Condition: Badly Dinged

Notes: Item has a minor cosmetic ding in one spot that would be on the interior of the truck bed when closed. Also this item is missing the rails. Would make a good replacement.

$1,047.94

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