This is the correct suction and discharge compressor service valves used on most 1970 and up Ford, Mercury & Lincoln products equipped with factory a/c using a York or Tecumseh compressor with Tube-O head that uses a #10 o-ring seal. O-rings are also used at hose connections. IMPORTANT NOTE - This set comes with 1 valve that is for the #8 (Discharge) hose and 1 valve that is for the #10 (Suction) hose and 2 #10 o-ring seals. Please double check your current valves and compressor for size (#8 and #10) and type (O-Ring and Tube-O).