IVY Classic 27001 Bi-Metal Lock Installation Kit With Guide Template for Steel And Wood Doors, Carded Adjustable guide template for easy and exact drilling with snap-lock arms for selecting door width and backset Adjustable plastic guide template fits 1-3/8-inch and 1-3/4-inch thick doors Adjustable plastic guide template fits 2-3/8-inch and 2-3/4-inch backsets Bi-Metal construction with M-3 cutting edge retains hardness, Cobalt Advantedge (Registered Trademark) Includes 1-inch and 2-1/8-inch bi-metal hole saws and arbor with HSS pilot drill