Discount for the new one in the app:

Have had good luck running the line under hot water in the sink and tapping the knot with a hammer. Smash it flat and then stand it on edge and smash it. That should undo or loosen the knot.

If they fit/work; the price is right compared to usual kite strap prices. https://chinooksailing.com/collections/footstraps

Try some of these: https://www.grasski.net/en/

All remotely reminds me of:

http://whike.com/en/

While we're at it; imagine a windsurf setup modded into a sailboat.

https://tiwal.com/

Looking for cost or performance.

Are these fins $5? Are these fins better then all others on the market?

I think Nobile used to have some tool less fins.

Atan are hand made in France. Somewhere is a video showing them make them.

USA source:

https://isthmussailboards.com/booties.html

Or buy them direct:

http://atan.fr/en/surfing-booties-6

A better look at them: https://youtube.com/shorts/TtCLq8YAalE

If your bar is like the one in the video; you could drill off the rivet head and remove the bar end to get to the insides. Replace with same size 3/16" or 1/4" rivet. Harbor freight has the big rivet gun for 1/4" if needed.

I just want to know; is there really more then one factory producing these spreader bars or are they all made at the same place?