Note:Square hole drill and electric drill are not included in the package. [Mortising attachment for drill press] 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. [Dual Use Support Bracket]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. [Bench Drill Mortise Accessories]Mortise converter is easy to install and remove, you can quickly install or remove yourself, saving you time and effort. [Premium Material]Square hole drill fixed bracket is made of all steel casting, 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! Note: If stored in a humid environment for a long time, it may lead to some surface rusting, which can be improved by simply wiping some protective oil. [Effective and Precise]With its precise design, the adapter ensures accurate and smooth drilling operations. Color: As Shown Material: steel Package Contents: 1X Square Hole Drill Bit Adapter Only the above package content, other are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.