Alvin Beam Compass

Includes two 13" Ungraduated Beam Bars and One Coupling to Accommodate Circles up to 48" diameter.

• Spring-loaded thumbwheel on the top of each slide assembly allows for smooth and precise adjustments
• Comes complete with interchangeable ruling pen, pencil and divider legs
• Includes spare leads and needlepoint
• Packaged in a protective case with clear cover