Product Description Lasting up to 50% longer*, these Metal-Cutting Reciprocating Saw Blades feature a patented toothform that delivers fast, smooth cuts for a range of metal cutting applications. Their Bi-Metal construction is designed to extend blade life and minimize blade breaks. From the Manufacturer DEWALT DW4808 6-Inch 14 TPI Straight Back Bi-Metal Reciprocating Saw Blade, Heavy Gauge Metal, 5-Pack