The check valves has already passed ISO9901:2000 quantity certification,They are of low price and high quality. CHECK VALVES SPECIFICATION THREAD TYPE MODELRATED FLOWl/minMAX.OPERATINGPRESUREkgf/cm2CRACKINGPRESSUREkgf/cm2<<> PTAmmBmmWEIGHT(kg)CIT-034025005:0.550:53/8'' 74230.2CIT-04602501/2'' 81290.4CIT-06 100250 3/4'' 91350.7CIT-081802501''114461.0CIT-103502501,1/4'' 133562.1 CIT-126002501,1/2'' ...