My analysis of these drill bits showed that they are truly outstanding for industrial drilling applications .The cobalt construction ensures long life and durability while the spiral design provides excellent performance for drilling holes in a wide range of materials. These drill bits are also available in metric sizes, making them suitable for a variety of projects. The only downside is that they may be a bit more expensive than some other industrial drill bits on the market. Overall, if you're looking for a reliable and high-quality set of cobalt spiral drill bits, this is an excellent choice..