Master Lock Universal Trailer Coupler Lock

Part Number: 379KAATPY

In Stock

$40.21

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master lock trailer tongue fits 1-7/8 inch ball 2 2-5/16 379kaatpy

master lock trailer tongue fits 1-7/8 inch ball 2 2-5/16

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0 trailer tongue lock master universal coupler

0 trailer tongue lock master fits 1-7/8 inch ball 2 2-5/16 379kaatpy

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Great Prices for the best trailer tongue lock from Master Lock. Master Lock Universal Trailer Coupler Lock part number 379KAATPY can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.

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Reviews (48)
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Master Lock Trailer Tongue Lock - 379KAATPY

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
Includes 2 keys per lock
Limited lifetime warranty

379ATPY Master Lock Universal-Fit Trailer Coupler Lock

4.4

48 reviews

5 Stars		(33)
4 Stars		(8)
3 Stars		(3)
2 Stars		(2)
1 Star		(2)

by: Jacob johnson 05/22/2014

Master lock coupler lock is so easy to use and give you piece of mind that your trailer is safe. This is my second one and I love it. Etrailer shipped it so fast I will be ordering from them again.

by: Joseph Hyche 03/19/2014

Product is as dedscribed and works well. Shipped ASAP

by: Jerry 11/06/2025 One Year Later

I bought this lock after my trailer was stolen due to a very cheap lock I had on it. This lock is easy to use and is solid. I purchased this over a year ago and have had no issues with thievery since.

by: Carl 01/28/2026

The lock fit well no play in it.

by: Matt 01/12/2018 One Year Later

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.

by: Gary 02/28/2020

I bought two of these to put on my pontoon boat and an enclosed trailer that will be stored on another property. I really like the design and after getting it out of the packaging it works great. I put it on my enclosed trailer and will also use the other one on my boat. The entire process worked well with the only glitch was the computer didn’t recognize shipping it to a different address. Jenny was great and was able to walk me through the process completely. I only wished I would have asked to have both locks keyed the same. Would have eliminated an additional set of keys. Still very pleased with the product.

by: Dr J 01/19/2020 One Year Later

Great product that is easy to install on the trailer hitch making it very secure.

by: Phil 08/06/2019 One Year Later

Product is ok. But if hit with a hammer could be broken off. Use is for trailer theft
etrailer, is a great supplier quick delivery great description

by: Reid 08/31/2023

doesn,t fit trailer tongue too tightly.still a deterant.but could easily be broken

Jenny N.

9/6/2023

An alternate lock to consider would be part # TMX77FR. It is a different style of lock that would allow you to tighten it down on the coupler.

by: Tod 06/06/2019

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.

by: Mike S. 08/22/2017

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.

by: Brian D. 06/27/2011

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.

by: Charles 12/18/2020

The lock was just as described. The price was very fair and it was delivered one day sooner than estimated.

Charles K. One Year Later

12/19/2021

The lock is still working as well as when it was new.

by: Tom 03/13/2019

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

Tom One Year Later

3/14/2020

Product is still as good like new. Its been exposed in rain and snow and still opens and closes like it was new.

by: Rob P 01/16/2012

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.

by: Freddie 01/18/2019

As expected, and fast shipping

by: Jeffrey 01/29/2022

Fast shipping, thank you

by: jerry6 07/30/2010

no problems easy to install and take off , gives some security for the trailer left in a parking lot over night. Worth the money

by: Brian 02/02/2025

Brian One Year Later

2/2/2026

No problems! works great

by: Dale 01/25/2024 One Year Later

Adequate. Doesn’t fit particularly well, but would work to slow down a thief. I suspect a strong blow with a hammer would take it off.

by: Laura 08/12/2011

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.

by: Lawrence 05/08/2021 One Year Later

I do not own this lock. Did not order

by: Darin 07/18/2021 One Year Later

Easy, secure, worth it every dollar.

by: Nathan 09/06/2020 One Year Later

Great product!

by: SC Duck 12/12/2016 One Year Later

Works fine.

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Info for this part was:

Updated by:

DeAnne T

Updated by:

Adele M

Updated by:

Laura H

Updated by:

Michael B

Video by:

Samuel H

Installed by:

Kurt W

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