The author remixed this model.
The following changes have been made:
1. 6 holes were added for M2 x 10 mm screws.
2. adjustment of the slider and its rail so that it sits firmly, with a (click)
3. adjustments to the inside of the body so that there is enough space for the screws.
4. adjustment of the sliders from 10 mm spring to 12 mm spring with more strength.