Yes, GunSkins are 100% waterproof. The high-performance vinyl is non-porous, which means that the material creates an air-tight seal that also prevents water from getting in or out. As a matter of fact, GunSkins are completely waterproof.
This also means that GunSkins is weatherproof, too. Rain, hail, mud, or ice will not cause any issues to the installation. No worries about peeling or losing adhesion. GunSkins was designed for durability and day to day use.