Normally closed.Direct acting. No minimum differential pressure to operate.Low and high pressure versions. Injected or cast aluminium body.BSP or NPT threaded connections. Acrylo-nitrile seats.Class H coils with internal use housings. It includes the terminals for the electrical connection.Connection for 1/2” BSP pipeline. For 220V and 110V: current rectifier and transient reactive overvoltage supressor.Quick or two-stage opening. Both are adjustable. 1st stage: Quick opening from 0 to 80% of the total adjustable stroke. 2nd stage: Adjustable slow opening up to 20 seconds, from the end of stage 1, up to full stroke.Shutoff in less than one second.