Four Cutter Spline Bits have a series of 13 Spline that slide into an equal but opposite set of Spline in the drive system of the Spline Drive Hammer. This positive engagement of Spline to Spline allows maximum transmission of energy from the Hammer to the Bit. Superior quality carbide nibs are vacuum brazed to a heat treated steel body resulting in four cutting edges which pulverize the concrete as the bit turns and pounds the work surface. Available from 5/8 inch to 1-1/2 inch diameters. 4 Cutter style bits are also available in Metric from 16mm to 38mm. One per package. FEATURES: 3/4 in. diameter, 4-cutter headSpline shank. Drilling depth 6 in.. Overall length 11 in.