The String Shield String Wax by Bohning is a silicone-based liquid wax made to extend the strength of your bowstrings. Unlike firm waxes that use friction to soften and absorb, this string wax penetrates the bowstring instantly without any heat. Sponge applicator is clean and easy. String Shield String Wax formula reduces string friction and enhances faded string colors. This odorless, waterproof wax makes your bowstring look and feel brand new.