LENOX Tools 1991560 T-Shank thick metal cutting jig saw blade, 3 5/8-inch X 3/8-inch 14 TPI, 5-Pack provides users with improved blade durability and long life in thick metal. Power Blast technology strengthens the blade to reduce breaks and increase durability. Patented T2 technology provides fast, efficient cutting in a range of metal cutting applications. Bi-metal technology flexes to resist breaking and extend blade life.