The 500A series 1/2-pipe air pilot valve employs the classic Humphrey diaphragm poppet valve principle. Its unbalanced air spring return design ensures reliable shifting and airtight sealing, whether in the actuated or non-actuated state. The compact design allows for close-proximity installation to the working area and enables rapid cycling/quick exhaust. The robust 2-way or 3-way valve features a standard brass valve body construction (for alternative media) and is normally closed.