Square Hole Drill Bit Adapter Holder Clamp Adjustable from 15-22 inches Durable Material: The square hole drill fixed bracket is made of high quality stainless steel material, wear resistant, high hardness, sturdy and durable. Fitment: The square hole drill bit adapter is fit for table drill and hand drill clamp with a diameter between 38mm to 55mm/1.5 to 2.2inch. Bench Drill Mortise Accessories: The square hole drill bit adapter converter is easy to install and remove, you can quickly install or remove it yourself, fast and convenient. Note: Square hole drill bit adapter, products do not include square hole drill and electric drill, use support bracket for table drill and hand drill. Wide Application: The square hole drill bit adapter bracket is perfect for woodworking and furniture making, ensuring accurate and smooth drilling. Specification: Material: Stainless Steel Clamp Diameter: 38mm~55mm/1.5inch~2.2inch Package Includes: Optional: 1 Square Hole Drill Bit Adapter or 1 Square Hole Drill Bit Adapter 4 Screws or 1 Square Hole Drill Bit Adapter 4 Screws 1 Nut Note: Please allow slightly errors due to manual measurement and different monitors.