Optimized for cutting steel, Klein's Bi-metal Hole Saws have the fastest, most consistent, and longest lasting blades on the market. The heavy-duty construction includes 5 mil back plates for durability and precision when cutting through drywall and ceiling tile. Recommended for major brands of 6 in. recessed lighting fixtures, these hole saws also bore through 2x4s in a single pass. For use, pair with Klein Tools arbor (cat number 31906), sold separately. Please note that the product may vary by store.