Graham-Field 3083DZ Grafco Hoffman Screw-Compressor Clamp for Flexible Tubing, Open Style, 1" x 7/8", Pack of 12

I'm thinking 2 use for addedsecurity for a Thule Sidekick roof cargo carrier tighten along the lips of clamshell. Do you think they will stay tight?

What is the max interior opening height of these?

will it slide over an 3.2 cm opening?

will it slide over an opening of 5/8"