Diablo, Demo Demon, 3 Pack, 6'', 6 TPI Carbide Reciprocating Blade With New Variable Tooth Design Specifically Designed For Maximum Performance In Nail Embedded Wood, High Performance Carbide Tipped Blades Deliver An Unmatched 50 Times Longer Cutting Life Than Bi-Metal Blades In Nail-Embedded Wood, Diablo's Patented Variable Tooth Technology Provides Faster Cuts With Less Vibration.