The FlushMount Drill Bit System incorporates a unique ball-bearing stop collar that controls the recess depth of the drill and allows the stop collar to stop spinning when it comes in contact with the surface. Includes a 9/16" carbide cutter. The carbine cutter has 3 sizes available: 3/8" Carbide Cutter, 9/16" Carbide Cutter, & 18mm Carbide Cutter.