Profile: Pople Industries manufactures valves, fittings & other components for instrument and process control industries. We offer check valve, which prevents reversed flow to protect solenoids, regulators & pumps. Our product line comprises of ball & needle valve, valve manifold, check valve, quick release coupling and tube fitting. Our pi-lock tube fittings are designed and manufactured to provide a leak-proof, torque free, seal at all tubing connections, hazardous leaks in process and instrumentation tubing.