Vast plumbing knowledge and expertise goes into every Superior Tool tube cutting wheel we make. Superior Tools proprietary SXT cutting wheels use a special annealed steel that provides a higher carbon content to provide deeper, uniform hardening capabilities. We painstakingly burnish the wheels cutting edge to ensure smooth, quick tubing cuts. Wheel edges are laser inspected for accuracy and quality. Each wheel is strengthened from hub to edge by cryogenic treatment and careful, slow tempering. Each wheel is treated with a special black oxide treatment to reduce friction and fight corrosion. Package contains two replacement cutter wheels.