Ruler Parallel Ruler Nautical Charts Parallel Ruler Mapping Points To Pull Parallel Ruler 450mm

The main role: Chartwork for drawing lines or course, the degree or amount of degree course .Two hands each holding a ruler of David, alternately moved in parallel.Usage: When the move operation, the appropriate force to suppress static hand -foot, one hand pushing moving feet, two feet alternately moved in parallel until the required position. Alternately moving, to prevent the static foot displacement.size:450mmMaterial:plasticcolour:WhitePackage Contents:1 * Chart parallel rulerOnly the above package content, other are not included.Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.