Bosch T321BF3 3-Piece 5-1/4 In. 12 TPI Speed for Metal T-Shank Jig Saw Blades 12 TPI tooth design for smooth, very fast cuts Bimetal construction for durability and long life Extra-long 5-1/4 In. overall length, 4-1/4 In. working length Proper lubricant is recommended when cutting metal 100 piece pack offers maximum value