The IRWIN Bi-Metal Reciprocating Blade Set contains a selection of blades that cover the most popular cutting applications. Wood cutting blades are great for roughing-in work and nail-embedded wood. Metal cutting blades cut all metals including non-ferrous pipe conduit, stainless steel and sheet metals. Contains the following 5 x Nail Embedded Wood Bi-Metal Blades 152mm x 6 TPI 4 x Thick Metal Bi-Metal Blades 152mm x 14 TPI 1 x Medium Metal Bi-Metal Blade 203mm x 18 TPI 1 x Nail Embedded Wood Bi-Metal Blade 228mm x 6 TPI