Ruler and protractor combination: Measure length and angle with an accuracy of 0.3. This protractor is suitable for DIY projects, woodworking, decoration, and machining. 360-degree measurement: The hinge mechanism allows a full 0-360 degree range for measuring inside and outside angles. Large LCD screen: Features a large full-screen LCD display with simple operation using three push buttons for easy measurement and reading. Power supply: Uses a CR2032 3V lithium battery with automatic power-off function. Designed for low power consumption and extended battery life. Lightweight and durable: Constructed with thickened and widened ruler made of high-strength nylon fiberglass material for excellent rigidity, wear resistance, and no deformation. Hold function: LCD display includes a hold function for convenient readings. Battery model: CR2032. Voltage: 3V. Operating time: Up to 5000 hours. Automatic screen shut-off: After 6 minutes of inactivity.