The innovation among drawing appliances for blackboards: This compass has a magnetic
foot with 3 strongly adhering magnets, which fix the compass to every magnetic
blackboard.
Finally perfect circles and arcs are guaranteed!
Chalk can be clamped easily through a safe spring-mechanism. Hence, slipping of the
chalk is avoided.

Additionally the compass is equipped with a cm- and
degree-scale. On one blade there is a turning handle installed that eases usage.