The Vinyl Tubing Leak Proof Couplers have barbed ends for securely connecting to standard vinyl and soft PVC tubing. Applications include connecting water return lines for recirculating pumps. Hose slips onto barbed end for secure fit. Must be clamped for secure connection. This Single-barb design provides a leak-proof seal. Black Nylon offers good tensile strength for general purpose applications, max. pressure 150 psi, temp range -40° to 200°F. Natural Polypropylene offers good chemical resistance, max. pressure 150 psi, temp range 32° to 212°F.