Bulk-pack jar of 50 units of #49016OX, used for old 1/2 NPS valves; 2nd stage inlet fittings; SAS LP seats; J-regulators; HP module seal. Brown Viton (Fluorocarbon) for pure oxygen service to 2,500 psi. The clear, screw top, plastic jars are reusable for general parts storage or O-ring refills. O-ring refill #49016OX.