The stuff I got from the RV supply link Maine Sail provided last time is like very sticky putty in a strip--can be molded to itself just by rolling it between your fingers. It's 3/4" wide and maybe .1 inches thick. I'm planning on using it as my surface "gasket" material and around screw heads and in the deck screw hole countersink. Overall, I like the gray color--it blends in with metal amd looks OK where it shows against the white gelcoat. And you can sort of cut it with a plastic blade to trim after it oozes.
2000 Beneteau 331
Northern Chesapeake Bay
Ambition is a poor excuse for not having enough sense to be lazy ~ Steven Wright