Material: Made of premium acrylic sheet, high hardness and long service life. Function: Designed to draw lines bearing line or course, the degree or amount of bearing line degree course line. Precise Scale: The scale is engraved, accurate and easy to see. A good accessory for drawing and measurement Good Transparency: Navigation Parallel Ruler has good transparency and does not obscure too much information. Easy to Draw: Two hands each holding a ruler of David, alternately moved in parallel. Sturdy links provide the right amount of tension for drawing a line parallel to another line or reference point. Material: acrylic fiber Color as shown Package Contents: 10 pcs Parallel Ruler Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.