The Wheeler 89 Piece Professional Screwdriver Set is perfect for installing scope bases, optics and other firearms accessories. The durable custom-molded case features (54) hollow-ground flat bits; (15) specialty bits; (8) Allen; (4) Phillips; (3) Torx; (1) 2-1/4" shaft. The hollow-ground bits have a concave shape that allows for insertion all the way into the screw slot for maximum contact. The kit also includes (2) non-slip, over molded plastic handles with a convenient hinged storage case complete with a bit location guide and is constructed from durable S2 tool steel. This product is covered by a limited lifetime warranty provided by Wheeler. Made by Wheeler™ Tools.