High Pressure Relief Valve (HPRV)
Design: High Flow, Tamper Proof Design, Direct Acting Pressure Relief Valve
Inline, Manual Pull Ring Overide or Vent to Atmosphere
Factory Preset Crack Pressures from 250 Psi
Optional Lock Wire
Size: 1/2" 
Configuration: Male and Female NPT, SAE, JIC, BSPT
Materials of Construction: Brass and Stainless Steel
Many standard seal materials
Available Cleaned for Oxygen Svc