Spacers for mounting traction boards

I got this universal traction board mounts for my roof rack. The spacers they come with are finnicky, with a metal sleeve, and washers on both ends of the turn knob. I wanted something simpler, for when i'm out on the trail and am taking the boards on and off. I didn't want to be juggling washers and collars. Also, I wanted something a bit flexible that I could tighten down, and wouldn't rattle. 

So I whipped up these that essentially do the spacer and washer's job at the same time, and will be easy to take on and off, and are big enough to not lose. 

I don't know if these will work with all universal kits, but from poking around, they look like they would. You can always resize them as needed as well. 

This is the kit that I got that I used them with: https://a.co/d/2y934ZF