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Replacement Box with LED Lid for Engager Breakaway Kit

Replacement Box with LED Lid for Engager Breakaway Kit

Item # HM20121
Our Price: $34.00
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Accessories and Parts
Shipping Weight: 0.84 lbs
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Hopkins Trailer Breakaway Kit - HM20121
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  • Reviews (27)
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  • Videos (1)
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Hopkins Accessories and Parts - HM20121

  • Trailer Breakaway Kit
  • Battery Box
  • Hopkins


  • Fits Engager Breakaway Kit (20099)
  • Wiring pigtail measures 24" long
  • Quantity: 1 replacement box with LED in lid

20121 Replacement Box with LED Lid for Engager Breakaway Kit

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Video of Replacement Box with LED Lid for Engager Breakaway Kit

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

Video Transcript for Review of Hopkins Trailer Breakaway Kit - HM20121

Today we're going to take a look at the replacement box with the LED lid for the engager Break Away kit. Now this part will replace a damaged box on the Hopkins Engager Break Away kit, part number 20099, which we do sell separately on our website. Basically if you pop the lid off here, you can see on the inside this is where the 12-volt battery goes and the battery again is not included, it's sold separately. Part number HM20008 and it is a related product on this product page.Now this box has a push to test battery feature right here on the lid. It gives you the fast and easy battery testing of the built in battery charger here in the box. The test button right down here at the bottom that says test and then right above it there's three LED lights above the button that'll clearly display the battery status inside the box, so basically when you push that test button if the green light lights up, that'll show you that it's fully charged.

If the red LED lights up, that'll mean it's a low battery and needs a recharge. And if the yellow LED lights up, that means it's charging. Each time you just push this test button to check the readings on the battery.Now if you notice on the inside, there's two sharp wires, a white and a red wire. These will connect to your battery. The red goes to the battery's positive post and the white wire goes to the battery's negative terminal.

You'll notice there's three long wires coming out the back. These wires are about 24-inches long. The black wire that comes out, this is for the trailer 12-volt auxiliary power lead, the blue wire is to the break away switch, and the long white wire is the ground to your trailer frame.A few dimensions on this box. Let me go ahead and put the lid back on it. Just snap the lid right into place and it holds it in there.

The widest point of it where the mounting is is going to be 6 1/8 inches. Overall height is about five inches tall and the total depth on it is going to be about 3 3/4 inches.But that should do it for the review on the replacement box with the LED lid for the Engager Break Away kit.

Customer Reviews

Replacement Box with LED Lid for Engager Breakaway Kit - HM20121

Average Customer Rating:  4.7 out of 5 stars   (27 Customer Reviews)


Exactly the replacement I was looking for to the damaged unit. etrailer provided excellent communication and delivery with suitable packaging. Nice work.

I had also lost my battery. Unfortunately e trailer could not give me either details on the size of the right battery nor even offer the correcy sized battery for the box. Now that was disappointing.


Hopkins Factory Replacement for their Engager breakaway electric brakes system with built in battery charger. I have these on a couple of my tandem wheel utility trailers. Exact fit to replace a damaged one. Simple installation and wiring hookup.
Use this item IF you need both the battery box and the battery charger to be replaced, or a new installation.
E-Trailer also sells just the replacement lid with charger attached if only your charger is bad ( a simple snap old lid off, snap new lid on install), and a box with plain, no charger lid, that you can use to replace a battery box with a broken mounting foot (just unsnap the new plain lid, and snap on the old one with charger) at a significant savings.
NOTE: I cover mine with a cheapo plastic bucket held on with a small bungee to extend life of the unit by letting the sun's UV eat the bucket, not the Engager box.


The product arrived broken. I realize it's not your fault.
Customer service was not very accommodating. I needed to used the trailer so I had to purchase another breakaway kit from a local store. Now I'm stuck with another kit that I don't need. I asked the girl if she could ship it overnight so I could get my trailer ready, she said no. Go through my records , you see that I spend a fair amount of money with you. Not my fault the part came broken but you made me feel like it was


Had this product for over a year and have had no issues. We did mount using rubber grommets to help prevent plastic from breaking in the future.


Bought to replace original equipment: easy to mount to frame, wiring matched perfectly. Believe all these units nowadays have the problematic sticker on the faceplate that leaks after time, sometimes right out of the box. Which allows moisture into the unit and corrodes all the contacts. To help prevent this I ran a bead of silicone around the edge.


I'm very pleased with the prompt service. This part is an exact replacement for the breakaway box that came with my trailer when I bought it new.


The part arrived in perfect condition and as advertised, it was an exact replacement for my broken battery box and charger. Thanks for everything.


Exact replacement for one that came on trailer. I'm just going to make a protective cover so people don't step on and protect buttons from UV rays.


Exactly like the original that came with the trailer. Makes replacement a snap.



Works great. Great quality as promised. Will buy from again.


Bought this to replace the old one on my bumper pull horse trailer. Good price. Received it quickly. Was easy to install and works well.


Rplacing one that was on a trailer for 6 months. Don't know why it went out. Have others on multiple trailers and haven' had any problems


Delivered Quick and as Advertised!!!


Received ahead of time, rain left off so I could install, etrailer videos are awesome


the box was fairly priced and delivered in timely manner.

this was a replacement box since my horses got curious and ate the top of my original one. it I installed quickly too


This product was a direct replacement and is still functioning perfectly! Thanks.


Great replacement


Replacement box worked perfectly...


Arrived early and was the exact part i needed great service.


Good pice, prompt service and fast deli very.


Quick service and perfect match..Thank you.


Great people to deal with


will work and do what i anticipated. t hanks


Very satisfied with the product.


Came quickly. Exactly as advertised. Super service.


Great product.

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