Attached to square bars great.

Not that bars are _that_ important to keep in a pristine shape, but it'd be nice to keep the paint where the paint should be

However don’t expect it to fit the bars I listed earlier very well.

Bar bent when securing kayaks after discovering instructions weren't clear for assembly using one vs two kayaks

The j-bars worked perfectly and I liked them so much I bought as second pair for our other kayaks.

The j-bars worked perfectly and I liked them so much I bought as second pair for our other kayaks.

I had to add foam padding for a more secure fit and to protect my cross bars.

I had to paint the underside with a rubbercoating because the metal would have scratched the aluminum cross bars on my car.

A much better design would be to have two securing loops on the inside of the vertical bar top radius so that the straps could be set in place for both boats prior to loading either

It will scratch the bars

The bolts included are not the same ones pictured in the instructions, by the way, and it's very confusing as to which part goes where