ATR check valves are suited for noncorrosive mineral-based oils and liquids. Designed for pressures to 5000 psi, they are available with SAE, NPT, or BSPP ports in sizes from 1/2 to 2 in. and custom sizes to 4 in. Constructed of zinc-plated carbon steel with optional materials upon request.Holmbury Inc., (440) 578-1070, www.holmburyusa.com