DIVERSE SIZE OPTIONS Includes sizes 3, 4, 5, 6, 8, 10, 12 and 16 mm to accommodate various drilling requirements. SAFE AND SECURE LOCKING Setscrew collar locks securely anywhere along the bit without causing damage to the bit or workpiece. WORKS WITH STANDARD DRILL BITS Designed for compatibility with standard drill bits, enhancing usability across different projects. ROBUST CARBON STEEL MATERIAL Constructed from carbon steel for durability and reliable performance in woodworking tasks. USE SCENARIOS Cabinetry and furniture assembly: use multiple collars to achieve repeatable hole depths for hinge screws, shelf pins, and hardware locations. Batch drilling across multiple pieces: position the collar consistently on each bit to ensure uniform hole depth and location across parts. Quick tool changes: switch between different collar sizes to match varying hole diameters on related projects, without changing bits.