Pop-action design keeps product loss at a minimum;Relief valve designed to automatically reseat firmly after discharge;Resilient seat disc provides "bubble-tight" seal;3149 relief valves incorporate integral pipeaway adapter with break off groove that protects the valve from piping stress damage;Optional pipeaway adapters have grooves that will break off to protect the relief valve from damage should excess stress be applied to the piping;3149 relief valves include weep hole deflectors, installed to guard against flame impingement on adjacent containers;Most are ASME rated for use with LP-Gas and anhydrous ammonia