Features: This square hole drill bit adapter is craft from quality steel , which is sturdy and durability for long term use; The support bracket is reliability and practical, suitable for bench drills and hand drills. It is ideal for woodworking, furniture manufacturing and other related industries The square hole drill bit adapter is easy to use. The precise 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 faster than mortise machine Crafted from durability alloy, this Square Hole Drill Bit Adapter fits most cordless drills for versatile woodworking tasks. Specifications: Component: Alloy Length:Approx.15.5cm/6.1inch Model: JSH2023 Clamping ranges: 3.8cm-4.5cm/1.50inch-1.77inch Inner Hole:11cm Applicable scenario: wood operate, wood hole drilling Package Includes: 1pc Square Hole Drill Bit Adapter note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.