1/4" BSPT 6000 Relief Valve 5.5 Bar Set - 6000/06/G/5.5 The Series 6000 is a high lift safety relief valve with atmospheric discharge suitable for air and inert gas applications. The flow is de-rated and measured in accordance with BS6759 Part 2: 1984. The valve re-seats by minus 10% of set pressure. Valves for higher pressure ratings are available. Safety valves are PED approved and CE marked.