These high-performance refills are engineered for superior durability and longevity. Unlike many competitors' products, BLACKJACK utilizes twelve strands of high-tensile Kevlar fiber the same material used in bulletproof vests for unparalleled strength and resilience. Each strand is individually impregnated with live butyl rubber, creating a completely sealed, waterproof repair that resists moisture, dirt, and debris. This superior construction ensures the repair is virtually invisible and eliminates stress on the tire's belts, extending the life of the tire itself. The 4-inch diameter refills are designed to handle a wide range of tire damage, providing a reliable solution for various fleet applications. BLACKJACK's commitment to quality means you receive a product built to withstand the demands of heavy-duty use. Invest in BLACKJACK TIRE REPAIR BJK-RE-460 and experience the difference of a truly permanent and effective tire repair solution, protecting your bottom line and ensuring your fleet remains operational. Choose BLACKJACK. Choose reliability. Choose efficiency.