Introduce Tape Measure

Tape measure is used in daily life tools. We often see steel tape used in construction and decoration, is also one of the necessary tools for the family. Divided into fiber tape, tape measure, soft tape and so on.
The tape can roll up because the spring inside the tape, when the measured length is pulled out, it is actually the length of the elongated scale and the spring. Once the measurement is completed, the spring inside the tape will automatically shrink, the scale also followed the contraction in the spring force under the action, so the tape will roll up.