Fits A-frame and straight bolt-on couplers for broad compatibility
Patented Cobra keyway system provides high security and resists key duplication
Manual operation ensures reliable performance without power requirements
Manufactured in the USA for quality assurance
Affordable solution for trailer security without compromising on safety
Summarized by Shop
Description
Model S175 is our most affordable trailer coupler lock because it slides right over the coupler flange. From an "A-frame" welded-on trailer coupler, to a straight bolt-on style trailer coupler, Model S175 fits them both and will provide a great level of security!
Designing the best coupler locks is not an easy task. We pride
Material
Metal
Lock Type
Manual
Key System
Cobra standard (patented tubular keyway)
Compatibility
A-frame and straight bolt-on trailer couplers
Item Condition
New
Manufacturer Type
Aftermarket, OEM
Summarized by Shop
4.8
53 ratings
5
4
3
2
1
Stout lock
The lock design is nice and solid. My particular trailer snout was about 1/4” wider than the throat of the trailer lock, so I had to do some grinding to get it to fit. After that it was as the description stated.
M
matthew · August 17, 2026
Great Lock, well built
I considered other options but this one fit my needs, it they can get through this one I'd be impressed, it isn't going to be easy.
S
Scott · April 23, 2026
Solid as can be
Very impressed with the quality of this lock. In this instance, you do get what you pay for.