Set them up at the right height and your bar will be allowed to bounce off / touch the rib cage (where the movement should go, at least according to eg Rippetoe (1)), yet leave the area further up protected. You should be able to easily wriggle out; verify with bar only first.
My squat rack has numbered holes, this helps my setup time when switching J hooks from squats to bench.
Set them up at the right height and your bar will be allowed to bounce off / touch the rib cage (where the movement should go, at least according to eg Rippetoe (1)), yet leave the area further up protected. You should be able to easily wriggle out; verify with bar only first.
My squat rack has numbered holes, this helps my setup time when switching J hooks from squats to bench.
(1) https://youtu.be/4T9UQ4FBVXI @ 8:40