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  1. Tonneau Cover
  2. BAK Industries
  3. Fold-Up - Hard
  4. Rack Compatible
  5. Flush Profile - Inside Bed Rails
  6. Aluminum
BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish
Special Savings on Select MX4, G2, F1, & FiberMax Tonneau Covers.
BAK Industries

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

Part Number: BAK48121
In Stock
$1,249.99
Tonneau Cover

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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 BAK48121 can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
  • All Info
  • Reviews (119)
  • Q & A (0)
  • Photos

BAK Industries Tonneau Cover - BAK48121

  • Fold-Up - Hard
  • Rack Compatible
  • Flush Profile - Inside Bed Rails
  • BAK Industries
  • Aluminum
  • Matte
  • Opens at Tailgate
  • Tailgate Lock

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.


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


448121 BAK Industries BAK Flip MX4 Hard Folding Truck Bed Cover

Replaces 486121

Installation Details BAK48121 Installation instructions

This Product Fits The Following Vehicles



California residents: click here


Ratings & Reviews

4.7

119 reviews
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.

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by: 04/03/2024



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by: 04/02/2025



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Looks great and was easy to install



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Was a easy install , only had it for a week



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Great product!



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I love it, I’ve owned three



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Good cover and easy to use



by:

Fits like a glove and looks great


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119
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See what our Experts say about this BAK Industries Tonneau Cover

  • Would BakFlip Tonneau Cover from Ford F-150 Fit 2015 Chevy Silverado 1500 6.5 ft Bed
    Tonneau cover fits are very specific. It's rare that a cover fits the same truck for more than a few years as the designs tend to change pretty frequently which means that there basically wouldn't be any cover from a Ford F-150 that would fit a 2015 Chevy Silverado 6-1/2 foot bed. For a BakFlip tonneau that fits your truck you'd instead want the part # BAK48121 which is a confirmed fit.
    view full answer...
  • Is Thule TracRac SR Compatible With BAKFlip MX4 Tonneau on 2015 GMC Sierra 1500 w/ 6-1/2 Foot Bed
    It is; the BAKFlip MX4 Hard Tonneau Cover # BAK48121 that fits your 2015 GMC Sierra 1500 is indeed compatible with the TracRac SR. The reason why is the MX4 installs inside your Sierra's bed rails, leaving the top free, and the TracRac installs on top of the bed rails so there won't be any interference. The correct part number for the ladder rack that fits your '15 Sierra with a 6-1/2 foot bed is the following: - Thule TracRac SR Sliding Truck Bed Ladder Rack # TH43002XT-781
    view full answer...
  • Dimensions of BAKFlip MX4/F1 When Folded Up on 2017 Chevy Silverado 2500 Short Bed
    Both the BAKFlip MX4 # BAK48121 and F1 # BAK72121 will take up about 26" - 28" from the cab-end of your 2017 Chevy Silverado 2500 short bed. So if your truck bed does measure 6-1/2' (which can slightly vary so you need to confirm on your end) then that leave you with about 52" - 54" of open space. The differences between these covers is that the MX4 has a matte finish on top of the aluminum cover while the F1 has a gloss finish and a fiberglass top on top of the aluminum cover. This helps...
    view full answer...
  • Best Tonneau Cover Style For Towing A Fifth Wheel
    The best tonneau cover option to use when towing is a retractable cover because it retracts into a canister so it doesn't block any of the view while towing. If you get a fold up cover it will block the cab window. If you get a roll up cover it will interfere with the trailer's overhang especially while turning. If you give me the year make and model of your truck I can make a recommendation.
    view full answer...
  • Height of BAK MX4 Folding Aluminum Hard Tonneau Cover BAK48121 When Folded Up Fully at Cab
    When the BAK MX4 Folding Aluminum Hard Tonneau Cover # BAK48121 that fits your 2017 GMC Sierra 3500 with 6-1/2-foot bed is folded up fully the total height of all panels at the rear of the cab will be approximately 5-inches above the bed rails. My contact at BAK confirmed this height dimension.
    view full answer...
  • Truck Bed Toolbox to Fit with BAKFlip MX4 Tonneau Cover on 2018 Sierra 1500 with 6-1/2 Foot Bed
    Actually we do carry a toolbox specifically designed to fit the BAKFlip MX4 tonneau cover, part # BAK48121, on your 2018 GMC Sierra 1500 with the 6-1/2 foot bed. It's the BAKBox, part # BAK92120. It can be folded down out of the way when you're not using it or turned into just a shelf instead of a box. I've linked a video for you to take a look at. It's with a different tonneau cover but it fits the same wth your MX4.
    view full answer...
  • Will BAKFlip MX4 Hard Tonneau Cover Clear 5th Wheel Hitch when Closed on 2018 GMC Sierra 2500
    In all likelihood, yes, the BAKFlip MX4 Hard Tonneau Cover # BAK48121 will clear your 5th wheel trailer hitch when the cover is closed. The parts of the cover inside the bed that hang down only do so by about 1.5 inches from the tops of the bed sides. Worse case scenario is you may have to either lower the head on the hitch or just remove the head by unpinning it from the center section.
    view full answer...
  • Recommended BAKFlip Hard Tonneau Cover For 2015 GMC Sierra Denali 2500 HD With 6 1/2' Bed
    For your 2015 GMC Sierra Denali 2500 HD with a 6 1/2' bed I recommend the BAKFlip MX4 Hard Tonneau Cover # BAK48121 due to it being all aluminum which will be extremely durable to the elements and keep the cargo in your bed secured unlike traditional vinyl covers that can be cut with a knife. The BAKflip MX4 # BAK48121 will offer 21" of clearance inside of your bed and has a very sleek folding design that will allow you to fold the cover when you are using your fifth wheel hitch and wont...
    view full answer...
  • Recommended Hitch For A 2019 GMC Sierra 2500 Denali 6.6' Bed With A Tonneau Cover
    The Curt E16 5th Wheel Hitch w R16 Roller for Chevy/GMC Towing Prep Package - Slide Bar Jaw - 16,000lbs item # C16667 will drop right into your OEM puck system and has an adjustable height of 15-1/4 - 18-1/4 inches. This will allow you to leave your hitch in place and roll down your bedcover. As for the Tonneau bedcover you have a few different options: For a retractable cover I recommend the Pace Edwards Switchblade Retractable Hard Tonneau Cover - Aluminum and Vinyl - Black Item #...
    view full answer...
  • Availability of etrailer Quad Fold Tonneau Cover for 2016 Chevy Silverado 3500
    Hi Bob; at this time we do not offer the etrailer Quad Fold Tonneau Cover for a 2016. We may come out with one in the future, but I don't have an ETA on when that might be since these are relatively new and a lot goes into adding additional fitment. The # e45DR only fits the 2020-2025 GM 2500/3500 with a 6-3/4' bed. Unfortunately, we don't have a low cost alternative for the 2016 either. The best I can offer right now for your Silverado 3500 is a tonneau cover like the BAKFlip MX4 # BAK48121.
    view full answer...
  • Recommended BAKFlip MX4 Hard Tonneau Cover for 2017 Chevy 2500 with 6-1/2 Foot Bed
    We just had BAK in last week and the BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish # BAK48121 is the newest model they have available. The part number from the manufacturer matches what you are asking about, our part number is just slightly different. I've attached the installation details for you. They recently started making this model with a tail gate flange that allows the proper seal when you close your tailgate without needing to lift the tonneau. That is...
    view full answer...
  • When Fully Open Do Panels of BAKFlip MX4 Lean Up Against Rear of Truck Cab
    Yes, the panels do lean up against the rear glass of the truck that the BAK Tonneau part # BAK48112 that you referenced installs on. I attached a picture that shows what that looks like. I also attached a review video for this cover for you to check out as well.
    view full answer...
    Image 1 for
  • What Tool Box Works with the BAKFlip MX4 # BAK48121 on a 2018 Sierra 2500 with 6-1/2 Foot Bed?
    I have an answer for you. The DeeZee Red Label Truck Bed Tool Box - Utility Chest Style - Aluminum - 8 Cu Ft - Silver # DZ8546 does not fit your 2018 GMC Sierra 2500 with a 6-1/2 foot bed. However, for a 100% definite combination of the BAKFlip MX4 Hard Tonneau Cover - Folding - Aluminum - Matte Finish # BAK48121 and a tool box, I recommend using the MX4 with the BAKBox 2 Collapsible Truck Bed Toolbox # BAK92120. It clamps directly onto the bed rails so you do not have to worry about...
    view full answer...
  • What Material are the Buckles of the BAKFlip MX4 Hard Tonneau Cover Made Of
    The buckles that you see in the attached picture that are used to secure the tonneau it's folded, flipped up, or closed position are made of plastic.
    view full answer...
    Image 1 for
  • Tonneau Cover Compatible TracRac System For A 2019 Chevy Silverado 1500
    Hey Mike, I can definitely help with this. You are correct that to make your TracRac tonneau cover compatible, all you would need to do is add the base rails and swap out the feet (modular sliders as Thule calls them). That said, the cost of these individual components can add up, and buying a whole new system does seem like the logical thing to do. You would need two of part # TA01-42004, two of part # TA01-42003, the base rail set # TH21781 and four of the knobs # TAKB-90030-1. With...
    view full answer...
  • 2016 Chevy Silverado 1500 6-1/2 Bed Ladder Rack Recommendation to Fit with Tonneau Cover
    We do have some ladder rack options to fit with the BAKFlip MX4 Hard Tonneau Cover # BAK48121 on your 2016 Chevy Silverado 1500 6-1/2' bed. I personally like the TruXedo Elevate Truck Bed Rack System # TX46NV because it uses standardized crossbars that have T-Slots so it's easier to install a wider variety of accessories. This installs using clamps like your current tonneau cover so you'll need to adjust your rails when you install this. If you're just needing a standard ladder rack that's...
    view full answer...
  • Would Tonneau From 2019 GMC Sierra also Fit 2015 Chevy Silverado 6-1/2 ft Bed
    Yes a tonneau like the BAK MX4 part # BAK48121 would fit both a 2019 and a 2015 Chevy Silverado and 2019 GMC Sierra 6-1/2 foot bed.
    view full answer...
  • Recommended Ladder Rack That Does Not Interfere With Hard Tonneau Cover
    If your Undercover Hard Tonneau Cover sits inside of the bed rails you would be able to add the Thule TracRac SR Sliding Truck Bed Ladder Rack # TH43002XT-781 which sits on top of your bed rails and allows the ladder racks to slide around on the base rails for more a customizable fit for a 2015 Silverado with a standard 6 1/2' bed. You will need # TH43002XT-782 if you have a 2015 Silverado 1500 with a 5 1/2' bed. To be able to fold the cover you will need to slide the legs of the ladder...
    view full answer...
  • Rack For 2019 GMC Sierra 2500 With BAKFlip MX4 Tonneau Cover
    Hey Charles, The BAKFlip MX4 Hard Tonneau Cover # BAK48121 or # BAK48122 for your 2019 GMC Sierra 2500 is compatible with one one rack that will allow you to carry a couple bikes, and that's the TruXedo Elevate. The right one depends on the size of your bed: - 6-1/2' Bed: TruXedo Elevate Truck Bed Rack System # TX46NV - 8' Bed: TruXedo Elevate Truck Bed Rack System # TX66NV The Elevate will essentially give you a roof rack at the rear of your truck, and the bars are adjustable, but...
    view full answer...
  • Ladder Rack Needed for 2015 Chevy Silverado 1500 6-1/2 Bed with BAKFlip MX4 Cover
    Since your BAKFlip MX4 Hard Tonneau Cover # BAK48121 sits inside the bed rails of your pickup we do have some solutions for you. The best option would be to use the Thule TracRac SR which is a sliding rack that mounts on top of your bed rails and has a weight capacity of 1,250 lbs. To fold your MX4 up you will simply need to move the legs out of the way along their tracks. For your Silverado you will need either part # TH43002XT-781 or part # TH43002XT-781EX if you want the over-the-cab...
    view full answer...

Do you have a question about this Tonneau Cover?


Info for this part was:

Employee Tyler C
Edited by:
Tyler C
Employee Michael H
Expert Research:
Michael H
Employee Jameson C
Expert Research:
Jameson C
Employee Adam R
Expert Research:
Adam R
Employee Dustin K
Video by:
Dustin K
Employee Shane H
Video by:
Shane H
Employee Jonathan Y
Video by:
Jonathan Y
Employee Chris R
Video Edited:
Chris R
Employee Zach D
Video Edited:
Zach D
Employee Hayden R
Test Fit:
Hayden R
Employee Jacob H
Test Fit:
Jacob H
Employee Wilson B
Updated by:
Wilson B
Employee Noah M
Updated by:
Noah M
Employee Ronnie R
Written by:
Ronnie R

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