Champion P02287A is a 5/8 in diameter unloader piston used in Champion's constant-speed head unloader kits for R-series air compressors, including the R40A. As a genuine replacement part, it operates within the head unloading assembly to vent air from the discharge passage when the compressor reaches its set pressure, allowing the motor to restart without fully stopping compression. This piston is part of the head-unloader kit family designed for Champion air compressors; confirm compatibility with your specific R-series model before purchasing.
