Astro 2181B ONYX Die Grinder Kit, 2-Piece SA-5: Cylindrical shape 1/2-Inch X 1-Inch SA-3: Cylindrical shape 3/8-Inch X 3/4-Inch SC-3: Cylindrical radius end 3/8-Inch X 3/4-Inch SC-1: Cylindrical radius end 1/4-Inch X 5/8-Inch SD-1: Ball shape 1/4-Inch