Features: Precise Hole Expansion: This high speed steel multistage alloy coated reamer offer precise hole expansion from 4mm to 12mm, eliminating frequent bit changes for model makers and craft enthusiasts. Durability alloy Coating: Features wear resistant alloy coating that increases durability by 50% and extends tool life by 60%, ideal for professional modelers working on complex projects. User Friendly Design: Optimized blade angles reduces resistance during operate, providing smoother performances and reducing hand strain for beginners and hobbyists. Multiple Materials Compatibility: Works effectively on plastic, and aluminum alloys, making it versatile for various modeling and crafting applications. Portable Storage Solution: Lightweight is for easy transport, perfect for model competitions or exhibitions. Specifications: Component: alloy Length:Approx.12.5cm/4.92inch Size:4mm-12mm diameter Suitable for materials with a less than 23°hardness, such as aluminum plates, plastic, and metals with a thickness of less than 2MM. Applicable scenarios: model modification, model installation Package Includes: 1pc Trapezoidal Drill Bit note: Please allow 1-3cm errors due to manual measurement. Due to the differences between different monitors, the picture may not reflect the actual item color.