1. Normally, all the insertion slopes of the slider are not allowed to be less than 3° to prevent excessive self-locking force and scratched;
2. The angle of the locking surface must be bigger than the angle of the angle pin by 2° or more;
3. For the slider driven by the angle pin, the inclination angle of the slider shall not over 30°;
4. The angle (A) of the angle pin shall not over 22°.