Durable bi-metal construction. A high-speed steel cutting edge extends cutting life, while a spring steel backing edge helps prevent breaking. Includes: (1) 6" 6TPI Bi-Metal Reciprocating Saw Blade(1) 6"14TPI Bi-Metal Reciprocating Saw Blade(1) 6" 18TPI Bi-Metal Reciprocating Saw Blade(1) 8"10TPI Bi-Metal Reciprocating Saw Blade(1) 9"6TPI Bi-Metal Reciprocating Saw Blade | IRWIN 5 Piece Multi-Purpose Bi-Metal Recip Kit