Bohning String Shield Wax .25 oz.. The sponge applicator is clean and easy and the String Shield formula reduces string friction while enhancing tired string colors. This odorless and waterproof wax leaves a like-new feel to the bowstring. Package Contents: Bohning String Shield Wax Silicone based liquid wax that instantly penetrates the bowstring with no heat necessary. The sponge applicator is clean and easy and the String Shield formula reduces string friction while enhancing tired string colors. This odorless and waterproof wax leaves a like-new feel to the bowstring.