T2 technology tooth design delivers up to twice the life and cuts heavy materials more easily. Bi-metal construction allows blades to bend and flex without breaking. Designed to minimize friction and heat build-up while cutting through the widest variety of metal materials. 14 tooth per inch blades are best for use with thick metals, metal demolition, fire and rescue. LENOX Tools Bi-Metal Reciprocating Saw Blade, 3 5/8-inch, 14 TPI, 5-Pack (20520314RC).