This Dac-308 Piston Ring is an original equipment replacement part and is designed to fit many model Oil-Free air compressors including DeVilbiss, Porter Cable, Sears, DeWalt, Snap On, Ex-Cell, Air America, Charge Air Pro, Dayton, Grainger, and many other private label air compressors and is a direct replacement OEM part. The DAC-308 Piston Ring is a preformed and specialy coated piston rings with the following deminsions: 48.00 mm Inside Diameter 62.50 mm Outside Diameter. This DAC-308 also supercedes the CAC-248, CAC-248-1 and CAC-248-2 Piston Rings and is designed to all of the current model connecting rods and cylinder kits including the KK-4835, KK-5081 and A02743 that have the replacable piston ring. The DAC-308 is also the replacement piston ring found in the K-0058 and the K-0650 Top End Rebuild Kits. The proper cylinder sleeve replacement kit must be used for the correct model number Air Compressor otherwise the unit may not operate properly or damage may occur. Please check the model and part number in your owner’s manual before ordering this replacement DAC-308 Coated Replacement Piston Ring.