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Megahitch Coupler Vault Heavy-Duty Coupler Lock - 2" and 2-5/16" Ball Coupler

Megahitch Coupler Vault Heavy-Duty Coupler Lock - 2" and 2-5/16" Ball Coupler

Item # UF35-946510
Our Price: $245.62
Trailer Tongue Lock
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Shipping Weight: 11 lbs
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Heavy-duty, solid steel coupler lock fully surrounds ball coupler to deter theft of your parked trailer. Powder coating resists rust and corrosion. Threaded ball easily engages ball socket. Includes 2" and 2-5/16" balls and 2 keys. Great Prices for the best trailer tongue lock from Ultra-Fab Products. Megahitch Coupler Vault Heavy-Duty Coupler Lock - 2" and 2-5/16" Ball Coupler part number UF35-946510 can be ordered online at or call 1-800-940-8924 for expert service.
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  • Reviews (11)
  • Q & A (0)
  • Videos (2)
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Ultra-Fab Products Trailer Tongue Lock - UF35-946510

  • Fits 2 Inch Ball
  • Fits 2-5/16 Inch Ball
  • Surround Lock
  • Ultra-Fab Products
  • Steel
  • Universal Application Lock

Heavy-duty, solid steel coupler lock fully surrounds ball coupler to deter theft of your parked trailer. Powder coating resists rust and corrosion. Threaded ball easily engages ball socket. Includes 2" and 2-5/16" balls and 2 keys.


  • Heavy-duty coupler lock deters trailer theft by preventing hookup
    • Threaded hitch ball engages coupler's ball socket like trailer ball does
    • Lock body fits over lip of coupler to block access to hitch ball socket
    • Lock core hidden underneath vault for additional theft deterrent
  • Adjustable design provides snug fit around your coupler
  • 2-Piece solid steel construction
  • Powder coat resists rust and corrosion
  • 2 Keys included


  • Application: 2" or 2-5/16" coupler
  • 1-Year warranty

Note: Not compatible with Bulldog couplers.


35-946510 Ultra-Fab Mega Hitch Coupler Vault Heavy-Duty Coupler Lock - 2" and 2-5/16" Ball Coupler

Video of Megahitch Coupler Vault Heavy-Duty Coupler Lock - 2" and 2-5/16" Ball Coupler

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

Video Transcript for Ultra-Fab Megahitch Coupler Vault Heavy-Duty Coupler Lock Review

Randy: Hey guys, it's Randy here at Now trailer security is a really important topic for a lot of the customers that I work with on a regular basis. Basically, securing your trailer is going to protect your investment, it's going to make sure that it doesn't disappear if you have it in storage, you've got it parked outside at night, maybe you're getting ready to go on a trip in the morning you've got your stuff loaded up, somebody hooks up to it and drives off with it. It can really ruined the whole situation.Basically, we're going to be taking a look at one of the more durable coupler locks that I've seen for a while. I've dealt with 30, 40 different coupler locks. And this one seems to be really, really well-made.

Now locks are there for a deterrent, that's why we have them. And I definitely think this looks like the tougher one to get through. I think this is really going to deter a lot of people, and it will protect your investment.It has a two-piece design. We've got an upper and a lower piece and a ball that's going to fit into your coupler. This is made to work with two inch and two and five 16th inch couplers.

Now this coupler lock is very popular with a lot of different trailering type people, especially Airstream owners. They really seem to be kind of drawn towards this lock in protecting their investment.Other trailers that we've tried outside, we've tried several utility trailers and enclosed trailers. The two and five sixteenths inch coupler that has that role on the outside, which can be a challenge, this fit really well on. The utility trailers that have the U-shape that go around the front and then the thicker wider latch that comes down this bit, right over top of we didn't have any issues with that. So it's going to work in most applications.The only one we really ran into any struggles with, is the Marine style surge style coupler.

That one gave us a few issues, but everything else it seems to work really well. Now as far as construction goes, it's really nice, really durable material. And in most of the trailer applications I found, it's going to sit pretty much like this. So if this is what you experienced, it's completely normal. So that's going to allow rain to get in here.As rain gets in here, they've got weep holes designed on each side.

That's going to allow rain to go through that first rib in there, or a securing rib, and then have holes on each side here on the bottom. That's going to prevent any moisture buildup in there, any issues that might come up with our lock. Now the lock's going to be located right here on the bottom. It's going to come with two keys. So let me get that in, rotate it, that allows us to remove that top section.And again, really nice thick material the entire way through. I really don't see any issues with this being deformed or anything like that, especially just standard use. So when it comes down to it, I like this. I think it's going to be a very, very good deterrent. And I like that it's constructed out of heavy duty steel, I like the powder coat finish on it. I think it will last a long time.The two things I don't like about it, it's a really big, heavy lock. You have to have room to store it and keep it inside your truck or inside your trailer when not in use. And I also kind of don't like where that locks located. I think being able to get in and underneath there and manipulate it while we've been doing it all day, just kind of annoying and having to get up underneath there.Now I know why they did it. It's reasonable. It makes it harder for thieves to get to it and do any kind of tampering or anything like that. And it's also going to keep it out of the elements. You don't have to worry about rain getting in there, you don't have to worry about a lot of dirt and debris falling down in it and settling in it, causing you issues when you operate it.The only thing I would kind of recommend to go along with this, if you're going to be doing long-term storage, if you're going to be an open storage lot somewhere, or if you're in a higher crime type area, I would definitely pair this with the etrailer wheel lock clamp. Essentially that'll be a two piece clamp that'll come around your wheel, you can secure it. And it gives you an extra level of protection.If somebody came up and saw this, I think it would deter them. But if they really, really wanted it, then they happened to see that other wheel lock as well, think having two different things that they have to defeat, it's at least going to take them more time to get through it, increases their chances of getting caught. Hopefully they'll think about it and move on to somebody else.Now as far as the installation goes, you'll want to get it set up for your coupler. That's really going to depend one on the ball size. We've got our two inch and also the two and five 16th inch ball. And it's also going to depend on your coupler's designed. So we're using the longer spacer here, with the two inch ball. On some two inch couplers if they're a little bit thicker on the top, like if they've got the latch that comes down and over, you're probably going to have to use the shorter spacer there, to give us a little bit more room on top.We've also got the option here to move this forward just a little bit. If we want it to be a little bit tighter or we can move it back just a little bit. We can actually take a look at that process now. We'll take that off, loosen up our bolt here. And I just had that hand tight. You will want to tighten that down just slightly. You need a 24 millimeter or a Crescent wrench for that matter to do that.Let me see when you take that down out of that hole, move it into this hole, and that's going to hold it in place. Prevents people from getting into it, being able to back it out. We can put our nut down and on. And that's going to bring it into our coupler a little bit further. On the ball, you can see that rounded top, the flat bottom. We want the flat bottom to go down. We bring that up and in, then we'll get our coupler latched. At that point, we just want to support the bottom and we can add the top. We come down and then use our key, get in there and lock it.So the idea with the different spacers, the different balls and that different positioning for that bolt, is essentially so we can get it on here as tight as possible. This would work in that bolt being in that rearward position, but we don't have to have it there. We can have it right here where it's up-front, gets just in a little bit closer. So I like the adaptability of it, I like being able to change those out, to get you as secure of a fit as possible.The only real trailer coupler that we've seen thus far, and we haven't messed with every single one on the market, but the only one we've really dealt with thus far that this isn't going to work with, is the Square Style Surge Couplers, the ones that slide back and in to the end of the trailer tongue. But that's the only real one we had problems with.And that was basically just because it didn't allow the top to come down quite far enough for that lock to latch. Overall, I think this is going to be a really good deterrent. Like any lockout there, it's not fail safe and no lock ever will be. If you're in a higher crime area, maybe do this, do the etrailer wheel lock that we discussed earlier. That should give you two forms of protection on your trailer, turn your trailer into a harder target to get to. I definitely like it. Save for that lock being on the bottom, which we discussed, but overall it's definitely going to be a harder lock to bypass than a lot of the other ones out there on the market..

Customer Satisfaction Score:

Customer Reviews

Megahitch Coupler Vault Heavy-Duty Coupler Lock - 2" and 2-5/16" Ball Coupler - UF35-946510

Average Customer Rating:  4.8 out of 5 stars   (11 Customer Reviews)

Heavy-duty, solid steel coupler lock fully surrounds ball coupler to deter theft of your parked trailer. Powder coating resists rust and corrosion. Threaded ball easily engages ball socket. Includes 2" and 2-5/16" balls and 2 keys.


I think this is one of the best hitch locks you can get. I've tried several others over the last 40 years.


I purchased the Megahitch Coupler Vault as an added level of protection for my Jeep trailer. I was pleasantly pleased with the excellent manufacturing of the vault. It is very solid and heavy, and well constructed. It may NOT be infallible, but will definitely slow the thief down, or, persuade them to move on. The cost is more than I expected, but the vault is of very good quality.


Works great! Deters thieves and looks easy to work with.


I just needed to have peace of mind knowing I could leave my vintage reconditioned airstream in a park for day’s without worry. The Vault is super rugged and the lock is not exposed. I don’t think like a thief but I would bet they think more then twice about taking this one because of the obvious challenge.


VERY Well made. Works well. It does fit my AIRSTREAM hitch well. Only issue, if it is an issue at all is that I have to adjust the ball every time I place it on the hitch, NOT a big deal and appears VERY VERY secure. A great deterrent


Added security for my trailer. I think it's a great product.


Beast of a lock. No way you can break this thing off. A year of use on my Topshelf Dump Trailer and I do not hesitate to leave on job sites.


Still the best lovk available. And I like the new key style


it's my 3rd one!




See what our Experts say about this Ultra-Fab Products Trailer Tongue Lock

  • Trailer Coupler Lock For Square Coupler With 2-5/16 Ball
    It sounds like you have an Unique Functional Product 2-5/16" square coupler which was bought out by Dexter. The MegaHitch Coupler lock part # UF35-946510 is designed to fit the standard sized coupler so it will most likely not be wide enough or tall enough to fit the square coupler according to Ultra-Fab. I recommend to measure the height and width of your particular square coupler and compare it to the Blaylock EZ Lock Trailer Coupler Lock part # BLTL-33-40D which has a inside width...
    view full answer...
  • What is the Strongest Coupler Lock and Locking Pin That Will Fit My Square Coupler
    I do have a recommendation for a coupler lock for your square coupler. I recommend the Fastway Universal Trailer Coupler Lock for 1-7/8", 2" and 2-5/16" Couplers # FA86-0015-318. I recommend the Fastway Universal Lock because it is made to fit various couplers, including square ones like yours. Also, the bolted lock is internal to prevent prying and the key mech is rounded to make it more difficullt to pick. Finally, it fits couplers up to 4" wide and the shackle is 6" long top to bottom,...
    view full answer...
    Image 1 for Image 2 for
  • Recommended Coupler Lock for the Titan Model 20 Brake Actuator
    I do have an option for you but the release handle on the Titan Zinc-Plated Brake Actuator part # T4750720 is going to limit the use of some coupler locks like the MegaHitch Lock Coupler Vault Pro part # UF35-946510. Instead, I recommend the Blaylock EZ Lock Trailer Coupler Lock part # BLTL-33-40D. In order to break though this lock you would have to cut though a 3/4" thick hardened steel pin which is easier said than done. This would require power tools but if a would-be thief does have...
    view full answer...

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Info for this part was:

Employee Lindsey S
Edited by:
Lindsey S
Employee Jacob T
Video Edited:
Jacob T
Employee Kathleen M
Installed by:
Kathleen M
Employee Randy B
Installed by:
Randy B
Employee Wilson B
Updated by:
Wilson B
Employee Eric H
Updated by:
Eric H
Employee Carrie F
Updated by:
Carrie F
Employee Zach D
Video by:
Zach D
Employee Kristina F
Written by:
Kristina F

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