The main body of the compass is made of plastic injection molding. The prominent function is to draw a straight line, and the hidden function is to draw a circle or an arc. The circle-drawing device is located in the middle chute of the compass. Easy and convenient, when we rotate the gear to move the device, it can produce an interesting interactive experience. When it is not used as a compass, it does not affect the function of the ruler at all. The ruler and the compass are always used in conjunction with each other. In the past, the two were separate and independent This time, we combined the ruler and the compass in a cute shape. The ruler is used to carry the compass components and the ruler and the ruler are integrated, which is easy to use and light to carry. Needle-free design to avoid stab injuries during use.