Pre-caution alarm valve,Valve,Pre-caution alarm valve,Pre-action alarm valve Item No.ZSFU100-4'',ZSFU150-5'',ZSFU200-8'' Pre-caution alarm valve,Valve,Pre-caution alarm valve,Pre-action alarm valveFeatures ... )4) Strength test pressure: 48 bars (4.8MPa) Pre-caution alarm valve,Valve,Pre-caution alarm valve,Pre-action alarm valve