PRECISION MATH COMPASS - Designed for mathematical geometry and art drawing. Features a unique design to help prevent slipping during use. PRECISE ADJUSTMENT - The adjustment knob allows students to create accurate geometric constructions. Compass can be locked in place for consistent performance. ADJUSTABLE SIZE - Draws circles with a maximum diameter of 10 inches and a minimum diameter of 1/8 inch. Suitable for various circle sizes. ALL-METAL CONSTRUCTION - Made from high-quality metal materials with durable build for long-term use. Includes three spare leads for easy replacement. STABILITY - Spring bow design with thumbwheel helps reduce unintended sliding during use. Color: Blue/Black Material: Metal Package Contents: 1 * Precision Compass 2 * Spare Screws 3 * Spare Lead Note: Light reflection and different display settings may cause slight color variations between the image and the actual product. Measurement may vary by +/- 1-3 cm.