The Performance Tool W7556 6" Precision Pencil Compass is a must-have tool for professionals and students alike who require precise measurements and near perfect circles up to 10 inches (250mm) in diameter. With its spring bow fulcrum, fine threaded rod, and center wheel, this high-quality professional grade compass is perfect for design work, math, geometry, art, drafting drawing, and more. The knurled thumbwheel with fine threads ensures exact sizing and resists movement, allowing for accurate measurements. Made from durable all-steel construction with a nickel-plated finish, chrome-plated needle point, and knurled aluminum handle, this compass is built to last. Additionally, the compass includes spare screws and 3 replacement pencil tips for added convenience, making it the perfect addition to any artist or designer's toolkit.