Parts List: 1×Fixed Bracket 6×Square Hole Drill Bits Highlight description: [What You Receive] The package includes 1 square hole drill bit adapter, and 6 square hole drill bits. The drill diameter includes 1/4 inch (6.4mm), 5/16 inch (8mm), 3/8 inch (9.5mm), 7/16inch (11mm), 1/2 inch (12.7mm), 5/8inch (16mm). The hand drill clamp diameter from 38 to 55mm/1.5 to 2.2 inch. Note: It is only suitable for bench drills and hand drills with clamps. [Premium carbon steel Material] The square hole drill bit adapter is crafted from carbon steel, sturdy and durable, which can hold wood firmly. It is about 6.3inch/16cm long, the upper inner diameter is about 0.75inch/1.9cm, and the lower diameter is about 2.17inch/5.5cm, reducing the use error. The drill bit will not be blocked by sawdust, which has high hardness, not roll, and has fast cutting speed. It is compatible with sharp, please take it out safely. [Easy to Use] The square hole drill bit adapter and drill bit set is easy to use. The precision design of the drill press mortise attachment ensures you can drill the correct mortises and tenons in the fastest way. It is more convenient and fast than mortise machine. [Suitable for Bench Drills and Hand Drills] The dual support bracket is reliable and practical, suitable for bench drills and hand drills. It is ideal for woodworking, furniture manufacturing and other related industries. [Widely Uses] You can combine the square hole drill bit adapter with 6 square hole drill bits and this simplifies the process of drilling square holes on wooden boards. It fits for construction, woodworking DIY, decoration industries, materials with lower hardness such as compressed board, plastic, density board, sandalwood, pine, ash, pine, etc. Detailed description: Description: Our square hole drill bit adapter and drill bit set is used for drilling mortises and tenons. It is easy to install and use, reliable and practical. It can reduce workload and suitable for beginners and workers. Feature: Square Hole Drill Sleeve: The force of the drill sleeve blade is effectively protected on a flat surface, which can avoid bursting at the beginning. Alloy Drill Bit: The drill bit is forged from alloy and has high overall heat treatment hardness. U-Shaped Chip Discharge Chute: The U-shaped chip discharge chute facilitates the discharge of wood chips and improves the drilling rate. Universal Round Handle: More stable clamping, suitable for square hole machines, square tenon machines, hand electric drills, etc. Specification: Product Name: Square Hole Drill Bit Adapter Material: Bracket: Carbon Steel Drill Bit: Carbide Specifications: 6.4/8/9.5/12.7/14/16mm Shank diameter: 19mm Color: Silver Grey Notes: 1.It is only suitable for bench drills and hand drills with clamps. 2.There may be slight differences between the picture and the actual color of the commodity. We will try our best to show you the exact color. 3.Please allow slight dimension difference due to manual measurement. [What You Receive] The package includes 1 square hole drill bit adapter, and 6 square hole drill bits. The drill diameter includes 1/4 inch (6.4mm), 5/16 inch (8mm), 3/8 inch (9.5mm), 7/16inch (11mm), 1/2 inch (12.7mm), 5/8inch (16mm). The hand drill clamp diameter from 38 to 55mm/1.5 to 2.2 inch. Note: It is only suitable for bench drills and hand drills with clamps. [Premium carbon steel Material] The square hole drill bit adapter is crafted from carbon steel, sturdy and durable, which can hold wood firmly. It is about 6.3inch/16cm long, the upper inner diameter is about 0.75inch/1.9cm, and the lower diameter is about 2.17inch/5.5cm, reducing the use error. The drill bit will not be blocked by sawdust, which has high hardness, not roll, and has fast cutting speed. It is compatible with sharp, please take it out safely. [Easy to Use] The square hole drill bit adapter and drill bit set is easy to use. The precision design of the drill press mortise attachment ensures you can drill the correct mortises and tenons in the fastest way. It is more convenient and fast than mortise machine. [Suitable for Bench Drills and Hand Drills] The dual support bracket is reliable and practical, suitable for bench drills and hand drills. It is ideal for woodworking, furniture manufacturing and other related industries. [Widely Uses] You can combine the square hole drill bit adapter with 6 square hole drill bits and this simplifies the process of drilling square holes on wooden boards. It fits for construction, woodworking DIY, decoration industries, materials with lower hardness such as compressed board, plastic, density board, sandalwood, pine, ash, pine, etc.