The Copeland Discus series of compressors incorporate the double walled Discus valve plate. The special design of the valve disk reduces clearance volume and may provide a considerable increase in performance, particularly in the low temperature range. The Discus series have a range from 0.5 to 70hp for use with R404A, R507, R407C, R134a and R22 refrigerants, offering broad application flexibility. Compressors are charged with Polyolester oil and are supplied with an internal oil pump, shut off valves and mounting kits along with non-active capacity control on 4, 6 & 8 cylinder models. Separate accessories include oil switches, crankcase heaters, capacity control kits and head cooling fans.