Sorby Thread Cutting Tool Set, 20 TPI is the starter package for anyone looking to learn the art of cutting threads on turned objects. Designed with a unique enhanced helix angle specifically for woodworking, these tools ensure smooth and precise results every time. I for making lidded boxes and other threaded turnings, the set includes a pair of thread cutters capable of cutting both male and female threads. Crafted with high-speed steel blades and ash handles, this set durability and comfort. Along with the thread cutters, you also receive a Thread & Sizing Gauge and the informative "Focus on Thread Cutting" DVD to help you master the technique. Model Number: A89HS20A