Profile: Compressor Valves & Plates Services is a manufacturer of compressor valves, air filters, oil filters, piston rings, cylinder liners and valve assemblies. Our valve seat & guards are made of stainless steel and nickel based alloys. We provide replacement pistons for reciprocating compressors. Our replacement pistons are made of graded cast iron, aluminum alloys, stainless steel and bronze alloys. Our piston sealing rings are used to prevent escape of gas from the pistons, and to prevent heat transfer from piston to outside through cylindrical walls.