Marine Type Approvals held for these valves: American Bureau of Shipping, Bureau Veritas, DNV, Germanischer Lloyd, Lloyds Register. Angular shaped spring loaded safety valves made of gunmetal with stainless steel spring Seal cap prevents unauthorized changing of set pressure. Suitable for the protection of pressure tanks and systems for air, neutral vapours and gases. Available models: 851 sGK with twist-type lifting mechanism, 851 sGL with lifting lever, 851bGFK with bellows and twist-type lifting mechanism, 851bGFL with bellows and lifting lever. Available seals: NBR, EPDM, FKM, PTFE, PTFE + carbon (standard from 25 bar ) , FFKM, metal-to-metal sealing. All models are also available in Stainless Steel: series 451. Model: 451 sGK with twist-type lifting mechanism