Rear Rack Question
 

I am buying these panniers.
https://cimg4.ibsrv.net/gimg/bikefor...3afc8d8e05.png

Are there any racks that WONT work? Some seem to have more substantial "sidebars" than others. Just don't want to order the wrong thing

Which rack do you have?

I don't. I guess what I'm asking is are there any rear racks this won't clip onto? I've noticed some side bars on the rear racks have more "stuff" on them. I'd really like to get one for $30 or less.

Do you have a bike?

This one needs a rack with left and right rails on the top, plus a set of "side bars" that form a "V." Pretty standard. I think I may not be understanding your question correctly.

Are those going on the beach cruiser?

This looks like an Ortlieb ripoff.
The rails on a rack won't vary in diameter by much. Ideally, the hooks on top will be a tight fit on the rails, to avoid rattling. Ortliebs come with shims that clip into the hooks to give you that tight fit. No idea if these panniers will, but judging from the picture, those hooks are way bigger than the rails on any rack I've seen.