Century Drill and Tool 7401 Cobalt Bi-Metal Reciprocating Saw Blade, 4-Inch by 18TS Cip-Saw Cobalt Bi-Metal reciprocating saw blades are designed for contractor grade applications Each blade consists of cobalt alloy high speed steel teeth electron beam welded to a lower alloy backbone provide a flexible, high performance blade For scroll cuts in ferrous and non-ferrous metal of 1/8 gauge - 1/8-Inch PVC and fiberglass Cip-Saw blades have C66-67 Rockwell hardened teeth which operates up to 10 times faster than carbon alloy blades Made in the USA