Product Description Packed with 3 different sets of blades with regular and fast-cut teeth, the DEWALT jig saw blades set equips pros for a range of cutting applications. T-shank design fits all Bosch and DEWALT jig saws. Includes a durable, clear case. From the Manufacturer Dewalt DW3741C 10 Pc T-Shank Jig Saw Blade Set with Case comes with three different sets of blades. The 6 and 10-tooth per inch blades are 4-inches long and are made with HCS material. The 18-teeth per inch blades are 3-inches long and made with Bi-Metal material. These blades feature regular and fastcut type teeth.