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This 5/16 in. Professional Mortising Bit is designed with a 5/8 in. shank to fit Delta Products. Contains 1 Chisel and Bit Set. Size: 5/16 in. square. Bits made of high-quality steel and resist overheating in heavy use.
Delta Power Equipment Corporation 17-002 5/16-Inch Professional Mortising Chisel and Bit Set - B007P1T2RE