Compass, Clear, Ø21 mm

A small transparent teaching compass, 21.5 mm in diameter and typically supplied in a box of 12. The clear housing makes the needle's movement easy to see, and the compact size lets you place several units close together on a flat surface to explore how a magnetic field spreads and points. Set around a bar magnet, the compasses let pupils watch each needle line up with the field, making invisible forces visible and concrete, a good support for understanding magnetism and electromagnetism, including how a field forms around a current-carrying conductor.