Size：Diameter 11/16”，cutting depth 2”，weldon shank 3/4”，pilot pin：1/4”*4” Annular cutters made with super tough m102al high speed steel (hss) for durability, wear resistance, high efficiency and superior service life Cnc-machined high precision annular drill bit set with 3/4 inch weldon shank (with 2 flats) for secure clamping and edge finish designed for smooth, reamed, burr-free edges of drilled holes. Use a firm steady pressure throughout the cut for better results Compatible with various brands of magnetic drills including alfra, bds, dewalt, euroboor, hougen, ruko. Caution: If you want to use this annular cutter on a drill press, you need an extra annular cutter arbor for the drill bit cutter. Arbor is not included in this pack Sturdy plastic case holding one annular cutter, one pilot pin