Ivy Classic 27001 Bi-Metal Hole Saw Lock Installation Kit for Steel and Wood Doors with Guide. Contains: 1" & 2-1/8" bi-metal hole saws & arbor with HSS pilot drill. The Guide Template with snap-lock arms for selecting door's width and backset (the distance between the edge of the door and the center of the lockset). 1 Inch Hole Saw for drilling the latch hole into the edge of the door. 2-1/8 Inch Hole Saw for drilling the hole on the face of the door. Arbor With 1/4 Inch Pilot Drill adapts hole saw for use with power drill.