Super Sawzall blades are made with Matrix II high speed steel teeth containing 8% Cobalt to keep a sharper tooth edge longer * Tough Bi-Metal design allows faster cutting, longer life blades that can bend without shattering * Manufactures Sawzall blades for the toughest professional applications * Heat treating designed to maximize performance in specific cutting applications * Blade has a 1/2" universal tang that fits all Sawzalls and standard competitive saws