In many applications, there is a need to limit the fluid flow to one direction. Check valves are the perfect solution for this need. Several versions are available, including our standard check valves, our non-metallic check valves, and even some specialized luer-based check valves. Check Valves are designed to effectively deliver a low cracking pressure. Most of our Check Valves connect directly to any 1/4-28 flat-bottom port. We created this unique design to eliminate the need for additional tubing cuts and connections to install traditional check valves. They accept fittings with 1/32", 1/16", 1/8" or 1.0 to 3.0 mm OD tubing.