Product description mr. Gasket copper seal exhaust gasket are made from 0. 043in solid copper. Help eliminate exhaust leaks in top fuel dragster, funny car, and alcohol class racecars. The height of the port is 1. 48in and its width is 1. 12in. They feature an embossed o-ring design to increase sealing pressure around the exhaust ports, creating a tight, leak-proof seal. They are also ideal for motor homes and towing.