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Master Lock Universal Trailer Coupler Lock

Master Lock Universal Trailer Coupler Lock

Item # 379DAT

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Master Lock Surround Lock - 379DAT
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Product Images

In Use/Installed

Videos


  • Surround Lock
  • Fits 1-7/8 Inch Ball
  • Fits 2 Inch Ball
  • Fits 2-5/16 Inch Ball
  • Master Lock
  • Keyed Unique
  • Universal Application Lock
  • Steel
Guard against trailer towaway theft with this universal-fit coupler lock. Durable steel frame fits around 1-7/8", 2" and 2-5/16" ball couplers, providing both a visible and mechanical theft deterrent. Lowest Prices for the best trailer coupler locks from Master Lock. Master Lock Universal Trailer Coupler Lock part number 379DAT can be ordered online at etrailer.com or call 800-298-8924 for expert service.


  • All Info
  • Reviews (16)
  • Q & A (19)
  • Videos (1)
  • Photos
  • Why etrailer?

Master Lock Trailer Coupler Locks - 379DAT

Guard against trailer towaway theft with this universal-fit coupler lock. Durable steel frame fits around 1-7/8", 2" and 2-5/16" ball couplers, providing both a visible and mechanical theft deterrent.


Features:

  • Deters trailer theft by fitting over the coupler, preventing hookup
    • Designed for use when trailer is not in tow
  • Constructed with a laminated, riveted steel frame for strength and durability
    • Center section that fits inside coupler is finned steel - will not warp or bend
  • Fits most 1-7/8", 2" and 2-5/16" ball couplers, including:
    • Straight lip, rolled lip and surge brake/hydraulic couplers
    • Reese, Fulton, Valley, Atwood, Shelby, Putnam, Bulldog, Dutton-Lainson and UFP couplers
  • Boasts integrated, weather-resistant cover that keeps dirt and moisture out of keyway
  • Includes 2 keys
  • Limited lifetime warranty


379DAT Master Lock Universal-Fit Trailer Coupler Lock





Video of Master Lock Universal Trailer Coupler Lock


Videos are provided as a guide only. Refer to manufacturer installation instructions and specs for complete information.




Video Transcript for Master Lock Universal Trailer Coupler Lock Review

Today we're going to be taking a look at the Master Lock Universal Trailer Coupler Lock, part number 379DAT. Deter theft of your trailer by preventing hookups. The Master Lock Universal Trailer Coupler Lock is going to fit most 1-7/8", 2", and 2-5/16" couplers. It's constructed with a laminated, riveted steel frame for strength and durability. The cover here is going to protect our keyway from dirt, debris, and moisture. Two keys are included. The adjustable center section fits inside your trailer's coupler, and the notches ensure a tight fit to many different styles of trailer couplers.

With it in place, we lock it with our key and we're all set. It features a limited lifetime warranty. That's going to complete our look at the Master Lock Universal Trailer Coupler Lock, part number 379DAT.


Customer Reviews

Master Lock Universal Trailer Coupler Lock - 379DAT

Average Customer Rating:  4.3 out of 5 stars   (16 Customer Reviews)

Guard against trailer towaway theft with this universal-fit coupler lock. Durable steel frame fits around 1-7/8", 2" and 2-5/16" ball couplers, providing both a visible and mechanical theft deterrent.

- 379DAT
by:

So far been great ,2 years and no problems easy to install and take off , gives some security for the trailer left in a parking lot over night. Worth the money 3302



- 379DAT
by:

Lock feels a bit cheap. Steel feels like Pot Metal. I dont think it would take too much effort for a theif to remove this. Fits on trailer pretty loose, moves around quite a bit. 29783



- 379DAT
by:

The ease of ordering was great and the product arrived as promised. The product itself was less than expected. It is made of plastic and I'm not sure it was the right choice. I will not return the product, but will look for something else that I feel is more substantial. 21673



- 379DAT
by:

This is the first of three trailer locks I've purchased that actually WORK for my trailer. Although I would prefer a heavier material for it to be made of, it works wonderfully. 17991



- 379DAT
by:

Great product. I bought originally for my travel trailer but ended up using it on my enclosed cargo trailer that lives outdoors all year. So far no issue with the lock seizing up from moisture or rust. 466788



- 379DAT
by:

Arrived on time as promised. Decent product. Quite loose in the fit more so than in the videos or so it seems. Still, it does block access to the hitch. Time will tell if it works to keep the scumbags from stealing my trailer. 423862



- 379DAT
by:

It gets the job done! I have a 14' flat trailer I like to keep in my driveway, this is the perfect fit for the job. I have large trailers and use the same type lock on those too. 654305



- 379DAT
by:

Product workeda expected. Very simple to use. Looks pretty sturdy and should last forever. 611391



- 379DAT
by:

Great price delivered quick and worked well... Thanks for the great service.. 608869



- 379DAT
by:

As expected, and fast shipping 598621



- 379DAT
by:

Love it! 515000



- 379DAT
by:

Good price, fast delivery. I'll shop here again. 460093



- 379DAT
by:

Works fine. 324300



- 379DAT
by:

Very quick delivery. Product was what I needed. 62483



- 379DAT
by:

Reasonable product - Reasonable price 22431



- 379DAT
by:

Excellent product. Works exactly as advertised. 100% satisfied. 12250


16
16

Ask the Experts about this Master Lock Trailer Coupler Locks
Do you have a question about this Trailer Coupler Lock?


  • Coupler Lock That Fits 1-7/8" Shelby Coupler
  • There is a coupler lock available for your 1-7/8" Shelby coupler, though they locks themselves aren't truly "universal;" oftentimes they say they will fit "most" but will name specific brands and types they fit. For example, the Master Lock Universal Trailer Coupler Lock # 379DAT will fit a 1-7/8" straight lip, rolled lip and surge brake/hydraulic couplers from Shelby, but also from Reese, Fulton, Valley, Atwood, Shelby, Putnam, Bulldog, Dutton-Lainson and UFP. There is also the Blaylock...
    view full answer...

  • Recommended Lock Options for Fultion Hand Wheel Latch when the Trailer is Connected to Tow Vehicle
  • Locking the hand wheel coupler to your vehicle can be tricky. You have a few options as you mentioned you can use a lock with the coupler removed from the ball of your vehicle like the Master Lock Universal Trailer Coupler Lock # 379DAT. To keep the trailer mounted to your tow vehicle and lock it, you will need to use an alternative lock than a coupler lock. I recommend the Blaylock EZ Trailer Wheel Lock # BLEZ-302. This prevents the trailer from rolling by attaching to the wheel...
    view full answer...

  • Coupler Lock for a Rockwood Signature Ultra Lite Travel Trailer 8312SS
  • I did some research on the 2013 Rockwood Signature travel trailers and it looks like the coupler is similar to a Bulldog # BD4425000317 but it was hard to tell from the pictures available on the internet. The Fastway Universal Trailer Coupler Lock, # DT25013KA, should work as long as the outside coupler width at the center of the ball is no greater than 4-1/2 inches. The sides of the Master Lock Universal Trailer Coupler Lock, # 379DAT, could interfere with the construction of the...
    view full answer...

  • Will Master Lock Universal Trailer Coupler Lock Fit a RAM 2-5/16 Coupler
  • I did a little research on RAM couplers. From what I saw, the Master Lock Universal Trailer Coupler Lock, # 379DAT, will fit the standard coupler type with a 2-5/16 inch ball size or the collar lock type that is more pointed at the end. If your coupler has a large lip around the outside where the lock would attach then it will not fit. If it does have a large lip but the width of the coupler from side to side is less than 4-1/2 inches, you could use # DT25013KA.
    view full answer...

  • Recommended Coupler Locks for Bulldog Cast Head Coupler # BDA256C0317
  • I pulled one of the Bulldog # BDA256C0317 couplers off the shelf, and tested it with various coupler locks. Other than the deadbolt style locks like the # RC6SS that pass through the latch, I found three locks that would work pretty well for you. The fit of the Blaylock EZ Lock # BLTL-33 was a bit loose, but once the locking bar was slid into place, I was unable to remove the lock by hand, although a pry bar might get it off. The Master Lock Universal Trailer Coupler Lock, # 379DAT...
    view full answer...

  • Coupler Lock Recommendations for Atwood Trailer Coupler # 80051
  • For trailer coupler 80051 you could use a latch lock such as # 7691 or # 2847DAT. These will install at the latch and prevent it from being able to pull up. Another popular lock for this coupler is # 379DAT. This lock has a part that fits inside the coupler where the ball normally would be. This prevents someone from coupling up to the trailer. I have linked videos for all three of the locks above.
    view full answer...

  • Coupler Lock for a 2 Inch Trailer Coupler
  • Blaylock Total-Encasement Coupler Lock # BLTL-22 is designed for Bulldog Collar-Lok couplers which are more narrow than regular coupler so I do not recommend trying to use it. I recommend using a coupler lock such as # DT25013KA or # 379DAT for your 2 inch coupler. I have linked review videos on both locks for you.
    view full answer...

  • Universal Surround Style Trailer Coupler Lock with Keyed Alike Option
  • I do have an option for you but the Master Lock Universal Trailer Coupler Lock part # 379DAT does not have an option to come keyed alike therefore I would not be able to offer you 6 of them with the same key. Instead, I recommend using the Fastway Universal Trailer Coupler Lock part # DT25013KA which fits 1-7/8", 2" and 2-5/16" couplers. This lock unlike the above option can be keyed alike therefore you would be able to order all 6 locks with the same key. I have attached a review video...
    view full answer...

  • Trailer Coupler Lock Recommendation for a Trailer with a Lunette Ring
  • We do have a lock for a lunette ring, but lock # 379DAT will not work. You will want to use the Blaylock EZ Lock, # BLTL-60. The 2 cylinders fit inside the ring and then a pin is placed through them and padlocked on one side so no one can hitch up the trailer without first removing the lock.
    view full answer...

  • Replacement Key Availability for Masterlock Coupler Lock 379DAT
  • For your trailer tongue lock part # 379DAT the correct part number for a replacement key is the part # MLK1. But you will need to know what key number you need. If you do not know what key number is needed there is no way to know.
    view full answer...

  • Coupler Lock Recommendations for a Titan Multi-Fit Coupler
  • You will need to take a couple measurements on your Titan coupler to be sure it will fit, but I would recommend you get a Tow Ready Gorilla Guard # 63228. This lock will slip on the front of your coupler and should work well as a theft deterrent. The width of your coupler (including the lip) should not exceed 3-13/16 inches and the lip should not be thicker than 5/16 of an inch. Another option you have would be the Master Lock Universal Trailer Coupler Lock # 379DAT, this will work similar...
    view full answer...

  • Will Master Lock 379DAT Work Well On Trigger Latch Style Coupler
  • Yes, the Master Lock Coupler Lock part # 379DAT that you referenced will fit and work well on the 2-5/16 inch coupler you sent in a picture of.
    view full answer...

  • Availability of a 2-5/16 Inch Trailer Coupler Lock
  • Yes, we have several different styles of coupler locks for the 2-5/16 inch coupler on your trailer. I recommend the Fastway Universal Trailer Coupler Lock, item # DT25013KA, which is one of the best coupler locks we have. We also have the Master Lock 2-5/16 inch Trailer Coupler Lock, item # 377DAT, and the Master Lock Universal Trailer Coupler Lock, # 379DAT, which are also very nice locks.
    view full answer...

  • How Tight Will Master Lock Universal Trailer Coupler Lock # 379DAT Fit on 2-5/16 Inch Demco Coupler
  • The Master Lock Universal Trailer Coupler Lock, part # 379DAT, is designed to work on all three hitch ball sizes, 1-7/8 inch, 2-inch, and 2-5/16 inches. Since it fits all three sizes it will not be able to be very tight, but you will want to make sure to slide the body of the lock up against the coupler as far as possible when attaching the lock to the coupler. As long as the lock cannot be removed after you lock it to the coupler it will work just fine in keeping somebody from connecting...
    view full answer...

  • Replacement Key for Master Lock Universal Trailer Coupler Lock 379DAT with Key Code 2434
  • The Master Lock Universal Trailer Coupler Lock # 379DAT does not allow us to specify key codes or lock cylinders and does not come with a keyed alike option. Additional keys are available for whatever lock cylinder you get using the Replacement Key for MasterLock Coupler Locks # MLK1 and entering the key number then the quantity desired.
    view full answer...

  • Recommendation of Trailer Coupler Lock to Fit a Titan 2-5/16 Inch Coupler
  • The Master Lock Universal Trailer Coupler Lock, part # 379DAT, you have referenced will fit a 2-5/16 inch trailer coupler. I also have the Master Lock Universal Heavy-Duty Trailer Coupler and Latch Lock, part # 3784DAT, which is the similar surround lock that goes over the front of the coupler, but it will also include a latch lock that can be used to lock the latch on the coupler for twice the security. Another coupler lock that is one of our top sellers is the Fastway Universal...
    view full answer...

  • Are There Replacement Parts for the Reese Tow and Store Lock Kit RP7014700
  • I wish we could sell you just the u-shaped portion of the Reese Tow and Store Lock Kit part # RP7014700 but unfortunately, the manufacturer does not allow for this therefore you will need to replace the entire kit. The other option you have is the Master Lock Universal Trailer Coupler Lock part # 379DAT which although would mean that you will have to carry another set of keys, will be a more cost effective option than replacing the entire kit above.
    view full answer...

  • Trailer Coupler Lock to Fit a 2011 Rockwood Signature Travel Trailer
  • I checked out the coupler on the 2011 Rockwood Signature Series Trailers online. The coupler is very different that other manufacturers, but I believe that we have an option that will work for you. The Fastway Universal Trailer Coupler Lock, item # DT25013KA, should work as long as the coupler width at the center of the ball is not greater than 4-1/2 inches. It looks to me like the sides of the Master Lock Universal Trailer Coupler Lock, item # 379DAT, would interfere with the construction...
    view full answer...

  • Can I Order a Reese Coupler Lock To Use a Key I Already Have
  • It sounds like you have a Reese Coupler Lock and are wanting to order another one that uses the same key you have now which is an A25. If that is the case then although I do not know exactly which Reese Coupler Lock you have (there are several), I can confirm that you would not be able to obtain this with a lock core that uses the same key you have now unless you were to randomly receive one for use with A25 keys which is not very likely. The most cost effective universal coupler lock...
    view full answer...


Do you have a question about this Trailer Coupler Lock?




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Info for this part was:

Photos by:
Theodore B
Video Edited:
Zack K
Expert Research:
Robert G
Expert Research:
Michael H
Expert Research:
Jeff D
Expert Research:
Jameson C
Video Edited:
Jacob T
Video by:
Dustin K
Installed by:
Hayden R

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