Package3 Pcs One Way Flow Pneumatic Check Valve, Push to Connect Air Tube Fitting for Air Compressor Dual Application:The pneumatic connector is used to connect polyethylene, nylon and PU tubes, air pipes and pneumatic tools, widely used in industries automatic equipment like machinery, electronics, automobile, packaging. Working Environment: 0-8 bars. Working Temperature: 0-60C. Applicable Tube: PU/Nylon/PE. Quality GoodsThis fittings are made of high quality plastic, durable and no air leakage for long term use. Built-in stainless steel locking claw and NBR O-ring, you'd never worry about that tube falls off. High pressure resistance, can withstand strong pressure without tripping, so no tripping needed. Easy to Intall No extra sealing is required, just a simple push to connect to the tube and they are tightly connected. Elliptical release rings at both ends are more convenient to disassemble without extra tools. In addition, those fittings are flexible and space-saving, 360-degree rotate freely.