This IRWIN 15 Pc Cobalt Alloy Steel Drill Bit Set allows you to drive through metal with complete precision. It's a versatile set that allows you to create different-sized holes in all sorts of metal. The Irwin Cobalt Alloy Steel drill bit set features 8 percent Cobalt Alloy Steel composition in order to tackle these materials. and it comes with a durable case for storage. The case protects your bits from drops and keeps them organized in a latching compartment with measurements listed. so it's easy to find the bit you need. The Irwin 15-piece drill bit set includes 135-degree split point bits that withstand pressure without cracking for long-term performance.