Used on sentinel class fast response cutter b (frc-b). 4.125" outside diameter gasket, blue guard 3000 cms data id 1972 pccn SE0413 plisn A010; next higher assembly 4810-01-620-5568 2-inch ball valve with actuator circular
fabric-reinforced silicone foam silicone rubber with fiberglass fabric center; purchased from marian inc who is supplied with silicone products by rogers corp or armacell