Professional Compass, 2 Pack Maths Drawing Precision Compass Geometry with Extra Lock Screws and Lead Refills for School, Home, Woodworking(Makes 24cm Diameter Circle)

Metal Material: Geometric compass made of all metal with a nickel-plated compass and a sturdy spring-loaded bow that is stronger than a plastic compass for long-term use. Maximum Diameter: Accurately make circles from 0.4cm to 24cm in diameter without the need to repeatedly use a ruler to measure diameters, angles and draw arcs. Precision tools: The fast and finely adjustable central drive wheel has an automatic locking mechanism that easily changes the radius of the circle and prevents the legs from moving during the drawing process. Adequate spare parts: The compass comes with an extra 6 spare refills, 2 spare fixing screws and 2 wing nuts for your use, plenty of replacements. Wide Application: Ideal for students, teachers, mathematicians, designers, artists, architects, engineers, metalworkers, leatherworkers and carpenters for drawing, drafting, etc.