Square hole drill bit adapter is fit for benchtop drill presses and hand drill clamp diameter ranging between 38 to 55mm/1.5 to 2.2inch, allowing for effortless installation and use. Your ultimate solution for enhancing the versatility of your table drill and hand drill. Square Hole Drill Bit Adapter is for table drill and hand drill. Square Hole Drill Bit Adapter is perfect for woodworking, furniture making, and other related industries. Mortise converter is easy to install and remove, you can quickly install or remove yourself, saving you time and effort. Square hole drill fixed bracket is sturdy. If you're looking for a versatile and efficient way to quickly install or disassemble drill accessories, then look no further than the Square Hole Drill Bit Adapter! With its precise design, the adapter ensures accurate and smooth drilling operations. Note: Square hole drill and electric drill are not included in the package. If stored in a humid environment for a long time, it may lead to