How does the tape measure roll up several meters of metal?

Under the hard plastic cover of the tape measure, 26 parts work together, and the tight coil spring enables the tape measure to measure data accurately.

The sleeve hook can hook the metal sheet without breaking the metal sheet, and the tight coil spring can absorb the metal sheet at the moment of friction.

At the end of the tape measure piece, the metal strip is attached to it, and the length is the same as that of the tape measure piece.As the metal strips wound around the central axle,

This becomes a strong spring. The more the tape is pulled out, the greater the pressure on the spring. As soon as the latch is released, the spring needs to be repositioned, and the tape leaf is immediately retracted.