IVY Classic 28204 J414P 4-Inch 14 TPI Metal Cutting U-Shank Jig Saw Blade, Bi-Metal, USA, 5-Pack Cuts metal 1/8-inch and above, Cobalt Advantedge (Registered Trademark) Bi-Metal with 8% cobalt matrix II alloy-steel cutting edge retains hardness Cutting edge electron welded to flexible, alloy-steel back for consistent quality Precision milled shatterproof teeth with Rockwell Hardness of 65-67 HRC. Made in USA, 14 TPI, 4-inch length x 3/8-inch width x .035-inch thickness