DEWALT DW3983 .020-by-44-7/8-Inch 18 TPI Portable Band Saw Blade, 3-Pack Matrix II High Speed Steel Edge for Heat and Wear Resistance 8% Cobalt Content For Added Durability & Wear Rc 65-67 Tooth Hardness For Increased Wear Resistance Alloy Steel Backer for Fatigue Resistance Matrix II high speed steel edge for heat and wear resistance 8 percent cobalt content For added durability wear Rc 65-67 tooth hardness for increased wear resistance Alloy steel backer for fatigue resistance