TAPERED CAPS AND PLUGS designed for a wide range of port sizes, protecting mating parts during service disassembly while sealing out dust and moisture. SILICONE RUBBER CONSTRUCTION ensures extreme durability and chemical resistance against automotive and industrial solvents. EXTREMELY FLEXIBLE, can stretch over bolts 3 times their size. EASY TO INSTALL with a simple Push-On / Pull-Off mechanism. TEMPERATURE RESISTANT for high heat applications.