Versatile and mechanical 7-segment display unit

Note : Improved single digit unit is released. Number of the parts is much reduced. It does not use rubber bands and requires very small force to drive.
https://www.thingiverse.com/thing:5066794

Summary

- A single unit of mechanical 7-segment display driven by a small hobby servo.
- This unit can be used solely as a kitchen timer, dice, single digit clock, etc.
- You can make digital clock, score board, counter, etc .. if you make two or more.
- Two versions are provided. One has digits in ascending-order, and the other is optimized. Latter one has a special order (1 7 4 5 6 0 8 9 3 2) to decrease the load to the servo with less flipping segments between neighboring digits.

Spec
- Overall size : 10cm (H) x 6cm (W)
- Digit size : 8cm x 4cm (area in the center lines of segments)

You need additional parts as follows
- Mini servo* (SG90 type : around 3USD per unit) comes with two screws
- Control circuit (I use micro:bit and breakout board Ks0360. Codes provided)
- 4 S