The 2W (UD/UW) series zero differential valves have the thread size range from 1/8” to 2”. AirTOP started the production when it is established. AirTOP has two types of these valves: brass body valves and stainless steel body valves, which can be normal close valve and normal open valve. With good quality and stable performance, this type of solenoid valves is widely used in many different industrial fields, especially water system.