Holyoke Fittings manufactures various needle valves, including models for hose, pipe and tube applications. These products are ideal for use in automotive, air conditioning, industrial, plumbing and refrigeration applications.

Aalborg Instruments & Controls, Inc. is a manufacturer of a variety of flow technogolgy components, such as VT PTFE and precision needle valves with structurally rigid metal shells and a simple seven component design.

Gruner Brass Fittings Corp is a manufacturer of a variety of needle valves. Models include flare to flare, angle needle flare to male pipe valves, needle valve compression to male pipe valves, and male pipe to flare angle needle valves.