2. Axial calibration on each diasc:165°~0°~180°~25°~ axis graduation line runs counter clockwise along axis
graduation line of lens frame, with interval of graduation line being 5°.
3. Degree that front lens rotates around optic axis inside lens frame: 360°.
4. Range of left or right lens frame leg's length adjustment:
90mm~99mm, length of specification of trial frame increase 1 mm in turn
