sleeves OR, PEFLEX Sealing rings Type designation Hydraulic valves VNRO, VNROI, VNROPT, VNROTP Non-return valves standard VNRCO Non-return valve plug-in cartridges VST and with soft seat VSOT Shuttle valves with ball seats VNROHP, VNROPTHP, VNROTPHP High-pressure valves VNRIO Internal valve part installation kits Excluded from type [...] exceeding 21% at 250 bar and 360 bar respectively. Sizes and pressure range Nominal pressure PN1 Nominal pressure PN1Tube O.D. mm L Series Tube O.D. mm S Series 6, 8, 10 500 6, 8, 10 800 12, 15, 18