Creative Engineers [M] offers Plastic Couplings with Single Check Valve. Creative Engineers [M] also manufactures various types of Pneumatic, Hydraulic and Special-purpose couplings under the brand name Rapilink which are used in flow lines for transferring variety of fluids at different temperatures and pressures. The Plastic Couplings with Single Check Valve, under the brand name Rapilink, offers large flow and a low pressure drop used in pneumatic and water applications. The Plastic Couplings with Single Check Valve has patent pending locking design which offers better locking at high pressure. The Plastic Couplings with Single Check Valve is made of plastic with Stainless Steel springs.