Pneumatic Quick Fittings - TOOGOO(R) 12Pcs Air Piping 2 Ways 6mm to 6mm Straight Hose Quick Joint Fittings Designed for using to connect with polyethylene, nylon and PU tubing. Simple push in design for connecting to the tube and provide secure connection, requires no extra sealing. Elliptical release ring on two ends facilitates pneumatic installations in confined spaces.