This is a high quality compass with automatic adjustment lever and jointed legs. Fast estimated adjustment is made by adjusting a lever found on either side of the leg. Finer adjustment is made by using the strong center spindle.

The extension bar can be attached to allow for circles up to 23.6 inches (600 mm) in diameter. The pencil adapter also takes pencils, colored leads or Indian ink refills up to 0.43 inch (11 mm) in diameter.