Primary Fluid Systems manufactures plastic back pressure valves for enhancing the accuracy of metering pumps.

JV Vissers Sales Corp. supplies diaphragm, high flow, and T-Series back pressure valves.

Metex provides ASCO high pressure 2-way valves for water applications. These valves come in sizes ranging from 1/4" to 3/4", and they can handle pressures ranging from 450 to 1500 PSI. They have an angled body design, a pilot operated/normally closed construction, and a variety of mounting options.