etrailer Boat Trailer Jack Mounting Bracket Measurements
Updated 04/13/2026 | Published 04/04/2026 >
Products Featured in This Question
Question:
Description says its for 2-4inch trailers, but later says its similar to a particular Fulton model, but only for 2inch x 4inch frames. Im guessing the second description is an error, right?
asked by: Chris
Expert Reply:
Apologize for the confusion Chris, I can clarify.
This is an error on our website, we'll get that information updated.
The # MJ-1200B clamps around the frame, so it can adjust to different sizes as long as the frame height falls between about 2" and 4". Because of the adjustable bracket, it typically works with:
2" x 2" frames
2" x 3" frames
2" x 4" frames
Up to about 3" x 5" rectangular frames
We advise measuring your frame height and width to confirm fitment.
How do you typically use the trailer; boating, work, camping?
Expert Reply:
Apologize for the confusion Chris, I can clarify.
This is an error on our website, we'll get that information updated.
The # MJ-1200B clamps around the frame, so it can adjust to different sizes as long as the frame height falls between about 2" and 4". Because of the adjustable bracket, it typically works with:
2" x 2" frames
2" x 3" frames
2" x 4" frames
Up to about 3" x 5" rectangular frames
We advise measuring your frame height and width to confirm fitment.
How do you typically use the trailer; boating, work, camping?

James
4/10/2026
Cris; I use my jack on my boat trailer. The trailer is a 4 inch frame. The jack is easy to use for this purpose. I'll recommend it for a boat trailer. I can't speak for other purposes. Sincerely James

Product Page this Question was Asked From
etrailer Boat Trailer Jack w/ Wheel - Sidewind - Swivel - 11" Lift - 1,200 lbs
- Trailer Jack
- Boat Trailer
- Utility Trailer
- Side-Mount Jacks
- Swivel Jacks
- Sidewind Jack
- 1001 - 2000 lbs
- Manual Jack
- 11 Inch Lift
- Bolt-On
- With Wheel
- etrailer
more information >
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Bob
4/13/2026
My boat trailer frame is 1.5" x 4" and the wheel jack fit just fine. Based on the bolt length and predrilled holes of my RAM jack mounting bracket, it should easily fit a trailer frame from 1.5 - 3.5" wide x 4 - 5" high.