LENOX Tools 1991478 T-Shank clean wood cutting jig saw blade, 4 1/2-inch x 3/8-inch 8/12 TPI, 3-pack provides users with improved blade durability and clean, smooth cuts in wood. Power Blast technology® strengthens the blade to reduce breaks and increase durability. Precision ground teeth with optimized tooth angles provide a clean finish. Bi-metal technology flexes to resist breaking and extend blade life.