Diablo Demo Demon, 5 Pack, 6" x 6-1/2" Tooth, Reciprocating Blade, Plunge Tip Design, Bi-Metal Ultra Hardened Cutting Edge, For Cutting Wood, Wood Composites & Nail Embedded Wood, Specifically Designed For Maximum Performance In Nail Embedded Wood Applications, Feature Bi-Metal Technology That Delivers Up To 4 Times Longer Life Of Standard Blades.