Take on a variety of projects with Spyder's Mach-Blue Drill Bit Set which includes 10 piece Mach-Blue Twist Drill Bit Set + 1/2-in Mach-Blue twist drill bit. The Spyder Stinger Mach-Blue Armor Plated high speed steel (HSS) bits are high performance metal and wood drilling bits that provide exceptional drill bit quality and durability, drilling performance, and value. The Mach-Blue armor plating combined with the advanced M-series alloy tool steel construction and proprietary heat treatment make these bits truly revolutionary - they retain sharper cutting edges for longer, have reduced heat build-up and cutting friction, and increased durability, rigidity, and breakage resistance. These incredibly durable bits are the Pro's choice for precision drilling, extended bit life, and value. Ideal for drilling stainless steel, mild steel, aluminum, wood, stacked materials and other difficult to drill alloys. The Mach Blue 10-Piece Twist Drill Bit Set includes 1/16, 5/64, 3/32, 1/8, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8-inch bits with case. Made in the USA.