Spool  type, two or three  position  direct  operated  valves  with  threaded  solenoids  certified  according the North  American   standart . 

solenoids are made by: 

. wet type  screwed  tube  ,different for AC and DC  power  supply ,with  integrated  manual  override  pin.

.interchangeable  coils, specific  for AC or DC power  supply, easily relaceable  without  tools -see  section  for  available  voltages