Pneuline Supply, Inc. offers Metal Needle Valves that have ports from 10-32 to 1 inch with a reduced thru hole size. A threaded tapered plunger allows precise regulation of flow. It is generally only capable of relatively low flow rates. They are adjustable to a flow of 0.025” diameter orifice. Needle valves are made with bodies of Aluminum, Brass, or Nickel-Plated Brass. O-Rings are Buna-N, Viton®, or EPDM.
Max pressure for metal needle valves is 180 psi up to 10000 psi with temperature of -40˚F to 200˚F.