Below are the various types of brass needle valves are made by us; 1. ff brass needle valve 2. brass drain cock, etc. Needle valves allow precise control from fully-off to fully-on. Manufactured from high quality dzr brass alloy, with viton 0-rings applications: suitable for fuels, water and air precision instrumentation hydraulic control systems anywhere precise control is needed working pressures: operating temperature 0 to 90oc should not be used where pressures exceed 3447 kpa (500 psi) where possible, pressure side should be toward valve seat, not spindle.