Alvin® 6" Professional Speed-Bow Compass Beam Bar Set
Made from zinc alloy with a matte chrome finish. Sturdy push button mechanism allows for quick adjustments, while the red spindle can be used for more finite adjustments. Features a double break leg for precise execution of circles up to 12" in diameter (up to 18" with included beam bar). Includes replacement lead and universal pen adapter. Packaged in a hard, see-through plastic case.