This FDA-certified, 0.178-inch thick, black sanitary gasket has an inside diameter of 0.38 inch and an outside diameter of 0.86 inch, for tube size of 1/2 inch. It has a Standard (Type 1) connection and is used with tri-clamp fittings. The working temperature is -35 Degrees F to 250 Degrees F. It has a tube hardness of 70A and is made of Buna-N and is oil, water, and mild chemical-resistant.