Bi lock installation kit. Bi-metal lock installation kit for metal door sizes 1-3/8" and 1-3/4". Back set sizes 2-3/8" and 2-3/4". Contains 2 bi-metal hole saws 2-1/8" and 1" with pilot drill bit. Easy guide template included. Material: Bi-Metal for Metal Doors, Door Thickness: 1-3/8" to 1-3/4", Backset Size: 2-3/8" & 2-3/4", Kit Contains: 2 Hole Saws,1 Pilot Bit,Guide Template, Pkg Qty: 1, Package Type: Clamshell