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Coupler Padlock for Roadmaster Tow Bars - Qty 1

Coupler Padlock for Roadmaster Tow Bars - Qty 1

Item # RM-305
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This coupler latch lock secures your Roadmaster car-mounted tow bar to the hitch ball on your RV or tow vehicle. Deters theft and gives you added protection from accidental release. 1/4" Diameter shackle fits most latch-style trailer couplers. 1-636-306-4830 to order Roadmaster accessories and parts part number RM-305 or order online at Free expert support on all Roadmaster products. Guaranteed Lowest Price and Fastest Shipping for Coupler Padlock for Roadmaster Tow Bars - Qty 1. Accessories and Parts reviews from real customers.
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  • Reviews (8)
  • Q & A (0)
  • Videos (2)
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Roadmaster Accessories and Parts - RM-305

  • Base Plates
  • Locks
  • Roadmaster
  • Keyed Unique

This coupler latch lock secures your Roadmaster car-mounted tow bar to the hitch ball on your RV or tow vehicle. Deters theft and gives you added protection from accidental release. 1/4" Diameter shackle fits most latch-style trailer couplers.


  • Padlock securely locks the coupler on your Roadmaster car-mounted tow bar to the ball on your RV or tow vehicle
    • Discourages theft and tampering
    • Protects against accidental release
  • High-security double ball locking mechanisms
  • Hardened steel construction adds strength and durability
    • Silver powder coated lock housings are rust resistant
  • Brass internal components and keys resist corrosion
  • 1 Padlock and 2 keys are included


  • Application:
    • Roadmaster car-mounted tow bars
    • Also fits most latch-style trailer couplers
  • Shackle diameter: 1/4"


305 Road Master Car Mount Tow Bar Coupler Padlock

Video of Coupler Padlock for Roadmaster Tow Bars - Qty 1

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

Video Transcript for Roadmaster Padlocks - Base Plate Lock - RM-305 Review

Today, we're going to be reviewing part number RM-305. This is the Roadmaster Coupler Padlock. It's going to be designed for use with steel master and tracker tail bars, but it can work on a variety of applications. It's going to feature a nice metal housing around the lock core right here, but you can see that it does leave the key hole exposed for easy access. It's going to come with two keys. It's a really simple and easy operation. All you got to do is place the key into there keyhole and then as you turn it and unlock it, it's about a quarter of a turn, it's going to disengage the shuffle of the pin from the lock body, so then you can place this through whatever application you want to use it on.

Then simple just push it back down into the lock house in there. It's going to come with two keys. They're going to be keyed alike, so you always have a backup. Now the shackle on the body are going to be made from a hardened steel construction for security, and it's going to do a good job when it comes to resisting rust and corrosion. A few measurements to go over with real quick to see if this is going to be a good fit for your application. Let me give you the measurements of the lock body, measuring this direction. It's going to give us a measurement of about an inch and a half. Measuring this direction, looks like it's going to measure about one and 7/8 of an inch.

Then right here it's going to measure about three quarters of an inch. Now, the overall length of this unit measuring from edge-to-edge, that's going to give us a measurement of about 5 inches. It's going to feature a quarter inch pin diameter, and then the opening size measuring from the top of the housing to the bottom of that shackle, that's going to give us some measurement of about 2 and fifteen sixteenth of an inch. Measure in this direction, the opening size looks to me about three quarters of an inch. That's going to do it for our review of part number RM-305. This is the Roadmaster Coupler Padlock. .

Customer Reviews

Coupler Padlock for Roadmaster Tow Bars - Qty 1 - RM-305

Average Customer Rating:  4.5 out of 5 stars   (8 Customer Reviews)

This coupler latch lock secures your Roadmaster car-mounted tow bar to the hitch ball on your RV or tow vehicle. Deters theft and gives you added protection from accidental release. 1/4" Diameter shackle fits most latch-style trailer couplers.


Works better than a bolt, but would not use for security. Coupling lock would be better, if security is priority,

I had one of these locks break from the force of the tow bar not sure if theyre strong enough to use on a tow bar.
-- comment by: Roger - 10/14/2012


This is not the first time we have used These guys are great! I can always find what I need at a fair price and they ship quickly!


It was snug, maybe a little too snug... had to sort of force it on in order to get the pin up. I would still rather have snug rather than loose.


Execelent service. Even picked the item on Sunday. Kept me in touch all the way. Great job.


Good locks


a good product works great


Exactly as advertised!



See what our Experts say about this Roadmaster Accessories and Parts

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Info for this part was:

Employee Matthew K
Installed by:
Matthew K
Employee Andrew L
Video by:
Andrew L
Employee Laura H
Updated by:
Laura H
Employee Shelly K
Updated by:
Shelly K
Employee Chris R
Video Edited:
Chris R

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