Professional Drafting Compass Math Geometry Set With Lock. Feature: PRECISION MATH COMPASS - Made for Mathematical Geometry and Art Drawing. Unique Design to Prevent Slip While Drawing. PRECISE ADJUSTMENT - The Adjustment Knob Enables Students to Produce Accurate Geometric Constructions. You Can Lock the Compass in Place and Have It Actually Stay when Writing. ADJUSTABLE SIZE - Maximum Diameter Up to 10 Inches, Minimum for 1/8 Inch. You Can Draw All Kinds of Circles. ALL-METAL MATERIAL - Made from High Quality Parts and Solid Construction, Durable Enough to Last for a Long Time. Three Additional Leads Are Easy to Replace when Needed. Stability: The Compass with Spring Bow Head and Thumbwheel Could Prevent from Unintended Slide. SPECIFICATIONS Model Number: New Material: Metal Type: Compasses Colour: Blue/black Package Contents: 1 * Precision Compass 2 * Spare Screws 3 * Spare Lead . We are an international seller, your order will be shipped from abroad so please allow the necessary time of minimum 14 working days for delivery right now depending on where you ship to, due to ongoing delays in postal deliveries globally.