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Master Lock Trailer Coupler Locks - Surround Lock - ML389DAT Review

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Review of Master Lock Locks ML389DAT

Today we're going to be taking a look at the Master Lock trailer coupler lock. This is a universal lock that's designed to fit most 1 and 7/8th inch, 2 inch, and 2 and 5/16th inch ball couplers. This is a heavy duty coupler lock that's going to deter trailer theft by preventing hookup. It's got a nice large size to it as well as the heavy weight. So it's going to defend against attempts to break or shatter the lock. It's going to use a wafer tumbler lock mechanism.

That's going to resist picking and prying. It's also hard to duplicate keys that would fit a wafer tumbler lock mechanism. The key hole right here is easily accessible. We're looking at a one-piece housing. This portion right here is going to be the portion that slides to fit tightly inside the coupler. I'll explain it just a little bit here.

Towards the end of the video, I'm actually going to show you how to install it on a coupler. So you want it in the open position. This is going to fit into the socket of the coupler. Then once you have it installed, you push these 2 pieces together. That's going to create the nice tight fit.

This is the one piece housing so that's going to slide to fit around the coupler and provide that nice tight secure fit that we need to make sure that it's all the way secured and to fully prevent trailer hookup. We're looking at a powder coated steel construction. It's going to do a great job at resisting rust and corrosion and lasting a long time. The red color is going to provide a visible theft deterrent, so in most cases, when a thief sees a lock installed, they don't even bother with it. So this is red in color and it's easily visible, and it lets people know right away that your trailer is hooked up and they're not going to go anywhere with it. So it's a really nice design. Over the key slot, we're going to have a key way cover.

That's going to protect the lock from moisture and debris. You're going to get 2 keys with a part number, and you're going to get one trailer coupler lock. Again this is designed to fit most 1 and 7/8th inch, 2 inch, and 2 and 5/16th inch couplers. It's going to fit standard lip, rolled lip, straight lip, surge break, hammer blow, and UFP couplers. With a maximum coupler width of 3 and one quarter of an inch. So be sure that the coupler width does not exceed that measurement. This is covered with a limited lifetime warranty. Now when installing this, it's a very simple installation. You want to make sure this is in the unlocked or open position. Place it into the socket on the coupler. I'm going to go and close the latch on mine. These 2 pieces slide together. Then I simply move it to a locked position. Then it's not going to go anywhere. It's fully secured and installed. Now you can see that it will rotate like that. But that does not give it any space to come off of the actual socket area. Removing it is also very simple. Place the key back in the key slot. Move it to the unlocked position. Pull it away, and it's going to drop right out. That's going to do it for today's look at the Master Lock trailer coupler lock.

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Info for this part was:

Employee Jacob T
Video Edited:
Jacob T
Employee Cole B
Installed by:
Cole B

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