Description Cobalt Drill Bit Set- 115Pcs M35 High Speed Steel Twist Jobber Length for Hardened Metal, Stainless Steel, Cast Iron and Wood Plastic with Metal Indexed Storage Case, 1/16″ – 1/2″ 115pcs Cobalt Bricks: This set is made of high-quality cobalt material, very hard and sturdy, includes 29 pieces Decimal sizes: 1/16 inch to 1/2 inch in increments of 1/64; 26 letters Size: A to Z; 60 piece numbered sizes: #1 to #60. Comes with a metal index storage box for convenient storage. 135° split point and twist design: The 135-degree fast cutting point is automatically centered for fast penetration with less pressure and less walking, and the fully ground drill bit has a sharp and sturdy cutting edge. The twist design clears debris faster and is built to withstand a variety of heavy uses. Good durability: Due to the properties of the cobalt, reinforced M35 alloy material, this brick has good resistance to corrosion and wear, and can be easily cut and drilled with conventional tools even in harsh environmental conditions, This allows your construction process to remain intact. Usage scenario: This cobalt brick is suitable for cutting stainless steel, steel and cast iron as well as wood, aluminum alloy and other metals, construction and decoration projects, such as wall painting, floor laying, furniture making, etc. Not only can it be used as an ordinary brick, but it can also be used to make various decorations and artworks, adding a unique style to your home and office space. Quality Commitment: Each cobalt brick is carefully packaged to ensure it will not suffer any damage during transportation.