Conrader Piloted Unloader valves combine a pilot valve and an unloader valve to run an air compressor for continuous operation. This can be used on gas engine or electric motor driven air compressors. HOW IT WORKS: In operation, the pilot remains closed until the pressure reaches the unload setting. The pilot then opens and pressurizes the unloader valve. This causes the unloader valve to open and vent the excess air from the compressor to the atmosphere. As the compressed air is used and the pressure drops to the load setting the pilot closes and depressurizes the unloader valve. The unloader valve then closes and the pressure begins to build again and repeats the cycle. Has Hand toggle have unloader and discharges pump air through felt muffler. For pumps without head unloaders and tanks with check valves. This brass valve is not deemed lead free.