NOS NOS bottom exit Pro-Race nitrous and fuel solenoids gives you the flexibility for mounting options in various positions. They are available with black or red powder coated top housing. All of our solenoids feature large orifice sizes for great flow. Our nitrous solenoids have a PTFE plunger puck material for durability while our fuel solenoids have FKM rubber plunger pucks for durability and sealing. All NOS solenoids feature stainless steel bases with the NOS logo along with in/out stamped in so you know it is a quality NOS solenoid.