Mr. Pen Bow Compass 4 inch 1 High Quality Professional Compass/Divider For Math, Geometry, Art, Drafting And Drawing, Creates Circles Up To 8 Inches In Diameter Precision Geometry Compass With Spring Bow Head And Center Wheel Prevents Unintentional Leg Movements All Metal, Nickel Plating Compass, Lifelong Satisfaction Guaranteed Easy To Adjust Legs, Great For Precise Drawings A Professional Choice