Thin Kerf Metal-Cutting Blades With The Double Duty Upgrade™ Feature A Tooth Form That Is Optimized For The Longest Life and Increased Speed. Tough Neck™ Is Engineered to Protect Against Tang Breakage and Delivers The Strongest Sawzall® Blade Tang On The Market. Maintaining A Short Profile and Thin Body, These Blades Are Ideal For Making Fast, Flexible Cuts.