BLUE BOAR 2-1/2" (64mm) MEGA Tungsten Carbide 2-1/4" deep hole saw TCT Hole cutters cut holes up to 10x faster and last up to 15x longer than bi-metal hole saws Mounts to all standard 5/8"-18 2-pin hole saw arbor adapters - Arbor and Pilot Bit Not Included 2-1/4" cutting depth recommend using with 18v Cordless Drill set on SCREW SETTING ****NOT for use with 1/2" stud drills such as Milwaukee Hole Hawg which will rip the teeth off **** Unique tungsten carbide tooth design wide kerf allows fast plug removal