These are replacement internal O-Rings compatible with Parker Series 9 pulse valves and Ideal Vacuum High-Speed Pulsed Solenoid Valves. The internal O-ring forms a pressure-tight seal which can withstand up to 250 PSIG between the valve body, which contains the output orifice or nozzle, and the solenoid coil assembly. These O-rings are made of chemically-resistant Viton® for use in vacuum or mild to moderate chemical environments.

See drawing below for internal O-ring replacement location.
_{Viton is a registered trademark of The Chemours Company FC, LLC.}