Features 1. Multiple Adjustable Diameters: This multi-diameter adjustable 1.77-5.12 inches (45mm-130mm) woodworking drill bit can cut holes of different diameters with a single tool, saving money and space. 2. CLEAN, FINE CUTS: Three three-tooth cutters cut through drywall and cork boards with ease, and their special straight serrations ensure clean, fine cuts. Three-knife design, straight round effect, smooth cutting without burrs. 3． Compatible tools: Hole saw approx. 10mm, suitable for all standard drills and cordless screwdrivers. 4. Multi-purpose: widely used in woodworking openings, spotlight openings, plastic plate openings, speaker openings, etc., but not suitable for glass and metal. 5. Easy to use: No complicated instructions for use. Stepless adjustment requires only three steps: release, adjust, and grasp. Specifications Material: Alloy Color: Blue Dimensions: 10.8 x 14.6 x 3.5 cm Weight: 450 g Package includes: 1 x Woodworking Hole Opener