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  1. Trailer Coupler Locks
  2. Master Lock
  3. Fits 1-7/8 Inch Ball
  4. Fits 2 Inch Ball
  5. Fits 2-5/16 Inch Ball
  6. Surround Lock
Master Lock Trailer Coupler Lock - 1-7/8", 2" and 2-5/16" Ball Couplers

Master Lock Trailer Coupler Lock - 1-7/8", 2" and 2-5/16" Ball Couplers

Retail:$46.05
Our Price: $41.64
You Save: 10%
Trailer Coupler Locks
Shipping Weight: 1.73 lbs
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Keep your trailer safe from towaway theft with this universal coupler lock. Its tough frame fits in and around most 1-7/8", 2", and 2-5/16" ball couplers; and it has a bright red color and heavy-duty construction to deter theft. Great Prices for the best trailer coupler locks from Master Lock. Master Lock Trailer Coupler Lock - 1-7/8", 2" and 2-5/16" Ball Couplers part number ML389DAT can be ordered online at etrailer.com or call 1-800-940-8924 for expert service.
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  • Reviews (832)
  • Q & A (0)
  • Photos

Master Lock Trailer Coupler Locks

  • Fits 1-7/8 Inch Ball
  • Fits 2 Inch Ball
  • Fits 2-5/16 Inch Ball
  • Surround Lock
  • Keyed Unique
  • Master Lock
  • Universal Application Lock

Keep your trailer safe from towaway theft with this universal coupler lock. Its tough frame fits in and around most 1-7/8", 2", and 2-5/16" ball couplers; and it has a bright red color and heavy-duty construction to deter theft.


Features:

  • Heavy-duty coupler lock deters trailer theft by preventing hookup
  • Large size and heavy weight defend against attempts to break or shatter lock
  • Wafer-tumbler lock mechanism resists picking and prying
  • 1-Piece housing slides to fit tightly around your coupler
  • Powder coat resists rust and corrosion
    • Red color provides a visible theft deterrent
  • 2 Keys included


Specs:

  • Application: most 1-7/8", 2" and 2-5/16" couplers
    • Fits standard lip, rolled lip, straight lip, surge brake, hammer blow, and UFP couplers
  • Limited lifetime warranty


Note: This product cannot be keyed alike.


Instructions for Locking the Trailer Coupler

  1. Insert key and turn clockwise to unlock.
  2. Pull the ball out from the lock body as far as it will go.
  3. Insert the ball of the lock into your coupler's ball socket.
  4. Push the lock body in so that it surrounds your coupler.
  5. Turn key counterclockwise to lock.


389DAT Master Lock Universal Trailer Coupler Lock - 1-7/8", 2" and 2-5/16"

Item # ML389DAT





Customer Satisfaction Score:


Customer Reviews

Master Lock Trailer Coupler Lock - 1-7/8", 2" and 2-5/16" Ball Couplers - ML389DAT

Average Customer Rating:  4.8 out of 5 stars   (832 Customer Reviews)

Keep your trailer safe from towaway theft with this universal coupler lock. Its tough frame fits in and around most 1-7/8", 2", and 2-5/16" ball couplers; and it has a bright red color and heavy-duty construction to deter theft.

by:

Very affordable deterrent that adds that little bit more security.



by:

Great locks!! I feel a lot better leaving all three of my trailers at home with these locks on my trailers! Definitely recommend!



by:

Doesn't fit securely. It seems like there are several ways to lock a trailer. Can't see how this one ever works well

Etrailer Expert

Jenny N.

3/22/2024

I hate to hear that you are not happy with the coupler lock. Would you be able to send a picture or describe in more detail how it is not fitting for you.



by:

It's a great product. It looks good on the trailer, and you can see it from very afar. And there is no way to saw it off, break it apart, or something like that. The construction is basically rounded, and there is nowhere you can find a starting point to place a saw or breakaway device on it. I have also bought different lock from Reese, and it looks wimpy, and easy to take it apart, or saw it off as some reviews have suggested. It's also easy to put it on and take it off. Just love the product. Here I attach some pictures in the campgrounds, etc.



by:

I have multiple trailers with different ball hitch sizes and Master Lock fits all of them well.



by:

The items arrived and were in perfect condition. But the most impressive thing about eTrailer is the great service and expertise that they provide. The items I purchased could have been purchased locally, but I prefer to purchase all the items for my trailer and related objects from eTrailer due to their superior service and advice.



by:

It went on and off easy. Seems well built time will tell.
etrailer was great to work with and it got faster than expected.



by:

Recently bought a boat and the trailer did not have any way to lock the tongue that I could see. After seeing that my stepson had a trailer with this style lock on it and seeing that it would be virtually impossible to pry it off I did some research. I have purchased from etrailer in the past and trust them to only sell the best. I ordered it and received it in a timely manner. It fits perfectly and I now feel my trailer and boat are secure. Who would doubt the Master Lock brand anyway!?!

Douglas

12/16/2020

Still working great, no complaints here.



by:

Fit my boat trailer perfectly



by:

Glad to see they went back to the original design. I have a chrome colored one I bought 13 years ago that is this style, still working. About 10 years ago I bought a 2nd one for my other trailer, and it was nothing like this one - cheap plastic everywhere, could easily be defeated. Backed into it once, and all the plastic broke off revealing just how flimsy it was. Was pleasantly surprised to see Master Lock went back to this much better design. I expect to get over 10 years out of this one.

Smithsonite

5/26/2023

Working great! No issues whatsoever. I keep the moving parts, including the key tumbler well lubed with white lithium grease, so this one is going to last.



by:

This is my second order from etrailers.com and the experience was rough due to the postal service on my first order but the staff was amazing at helping me work to find the shipment and even called my local post office. I was sold on this company and now my church uses them for all our trailer needs. They are extremely good at communications and updated me every step of the way including who worked with my package and even contacting me to ask if I wanted an alternative part that would have been here sooner. I love working with this company!



by:

Doesn't fit on a 2 5/16 equipment trailer. Made for small, lawn-mower trailers.

Etrailer Expert

Sierra K.

7/22/2022

I am sorry this coupler lock did not work for you. I think the hump on top of your coupler is the culprit. I think item # C48CR would fit better.



by:

It’s not exactly like we want. But for a lip roll tongue it fits. Wish they made the others for lip roll tongues instead of flat tongue…



by:

Universals lock, great for many applica tions



by:

Good strong product. Simple to use.



by:

Got this coupler lock for my boat trailer, easy to put on and take off.
So far it is working as expected, as do all the products I have purchased so far from etrailer.



by:

I feel much better about parking my trailer on the street with this lock on the hitch. Not only does it lock up the hitch securely but the bright red color signals to prospective thieves that this trailer cannot be towed.
It is easy to attach and easy to remove. Also very compact so it can be stored easily. The shipping time was less than I expected. etrailer.com is my goto supplier for my trailer accessories.



by:

Great easy to use



by:

I received the Master Lock Trailer Coupler Lock that I ordered. It was delivered in just a few days just a it was supposed to. It is exactly what I was looking for. It will help detour anyone from stealing my trailer ! I am extremely happy with the lock and etrailer ! I think this is a great company with great pricing on there products ! I will recommend them to everybody and will be ordering with them again real soon ! It was an easy and excellent experience. Great customer service too ! Thanks etrailer !



by:

Must be working... my trailer hasnt been stolen. I use every time in storage and at campgrounds. Easy to use.. Adjusts to fit snugly to coupler.. Doesnt bind up when installing or removing.. design much easier to use than some others.



by:

Went right on my hitch, Thank You



by:

This is a terrific design since unlike padlocks, can't easily be cut with bolt cutters. I like the bright red color which tells a thief there is a lock to deal with from a distance. I think someone who wants your trailer can probably defeat any system you use, so the goal is to make it tough as possible and I think this lock does that.



by:

So far the product looks, feels and works great. Shipping was very fast.



by:

Nice tool, I like that it will adjust easily for different depths so it will fit more than one size trailer tongue. It pulls in snug and with a couple firm smacks with a 2 pound hammer is still works just fine.



by:

Universal lock


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    The Master Lock Trailer Coupler Lock # ML389DAT will work well on your Big Tex 70DM 18 car trailer. I looked up pictures of the trailer and found that it has a collar lock style coupler which we know this lock works great with. I attached a picture of this lock used on a similar coupler for you to check out as well.
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  • Does Master Lock Trailer Coupler Lock # ML389DAT Come with a Cover for the Key Hole
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