High quality aluminum alloy materialMade of high quality aluminum alloy material, high strength and long service life. Made with aluminum alloy body and hard steel drill bushing for durability and precise use. Drill Guide Tools This is a set of tools Drill guide for fixing and centering drilling and woodworking. For fixing and centering when drilling and carpentry. Centerline ensures precise alignment when drilling on a variety of surfaces. By holding the drill guide body, vertical holes can be drilled without deviation. [Drill Sleeve Size] The drill guide has 6 drill guides with a diameter of 5mm, 6mm, 7mm, 8mm, 9mm and 10mm. Replacing the sleeve threads in the drill guide is very simple. Equipped with 6//7/8/9/10mm drill sleeves, suitable for different operations. Easy to use: simply select the appropriate size drill bit and stop ring, slide the stop ring on the drill bit and set the desired depth with a ruler or depth gauge (not included), then use the included Allen wrench to tighten the eyebolt; the clamping screw protrudes slightly (be careful when using near vertical boards). Wide application: The center line ensures precise alignment when drilling on various surfaces. The hole gauge is a great tool set for furniture makers and woodworking enthusiasts. Can drill round workpieces, corners, etc. Note: The data is all measured manually, please allow 1-3cm error due to differences in light and display, there may be some errors. have color differences, please refer to the actual item received.c