Originally Posted by offshoredrillin

Hey J, you can do it over both, it works best on the smoothest surface. most have a 9H hardness, it would still work on a porous gel, but it would soak up a ton of product and not last as long. I have used most of them and an am now using Xpel fusion plus, out of all of them it has the best properties and smoothness, plus it is formulated to not have high spots if one does arise it can be reactivated to get rid of it, the ceramic molecules form a hard ceramic bond to protect and comes with a 4 year warranty. it can go on metal, glass, chrome, plastic and rubber.. we are testing now on seats and vinyl, im sure the tiger interior will be the test mule for it