Voltage: 4.2V Speed: 5000-18000r/min Clamping Diameter: 2.35mm (Suitable for all 2.35mm specification grinding heads, drill bits, etc.) Improved Wireless Electric Grinder Pen: This grinding pen features a built-in rechargeable lithium battery, allowing for cordless use. With 3 speed settings ranging from 5,000 to 18,000 RPM, this tool delivers versatile performance for various applications. The three-speed adjustment allows precise control for different tasks, enhancing efficiency and precision in your work. Dual Usage: Supports both battery operation and continuous use while charging, enabling uninterrupted power supply for increased efficiency. Package Includes: 1 x Engraving Pen 1 x USB Power Cable 2 x Drill Bits 3 x Saw Blades 30 x Grinding Bits 1 x Tungsten Steel Bit 1 x Connecting Rod Note: 1. Fully charge before first use. 2. Not intended for carving, punching, cutting, or heavy grinding. 3. Normal operational noise and heat generation may occur during use. Color: As Shown Material: Metal Package Contents: 1 x Engraving Machine Set (accessories included as listed) Note: Lighting and display differences may cause slight color variations between the product image and actual item. Measurement error allowed is +/- 1-3cm.