Saw sharpening takes practice. Rather than take your first passes with a file to your Lie-Nielsen Saws, warm up on these Practice Plates. Each plate is made from the same quality Swedish Steel used in our Dovetail and Carcass Saws, with 7ppi on one edge, and 13 ppi on the opposite. We recommend a 7" Slim Taper File for filing 7ppi, and a 5" Double Extra Slim Taper File for 13ppi. Sold in packs of five.