Crown Automotive 4638904 Rear Output Oil Seal for 85-98 Jeep Wrangler YJ, (Grand) 4638904Cherokee XJ, ZJ & Comanche MJ with Model NP207/NP231/NP242/NP249 Transfer Case

gasket is a shaped sheet often made from rubber, paper or cork. Its role is to fill a space between two parts and act as a seal, thus preventing leakage into or from the parts when under compression.