1. Range of PD adjustments: PD of both eyes 48 ~ 80mm Minimum graduated value 1mm
2. Dividing disc axial graduation: Left dividing disc 1200 ~ 00 ~ 1350 Right dividing disc 450 ~ 1800 ~ 600 Axial graduation increases along the lens frame axis counter clockwise, and the graduated distance is 50
3. Inner diameter of lens frame: F32.5mm
4. Number of lens, which can be inserted into left or right lens frame simultaneously: 4 pieces
5. Degree of lens rotating around optical axis in the lens frame: 3600
6. Nonparallelism between lens optical axis and lens frames geometric axis: ??2.50
7. Non-concentricity between lens optical center and lens frame geometric center: ??0.5mm
8. Displacement of lens in relation to position of lens frame geometric center: ??0.3mm
9. Range of nose rest adjustment: Length: 0 ~ 14mm; Angle: 0 ~ 30 degree
10. Range of left or right lens frame legs length adjustment: 98 ~ 135mm
11. Maximum interval between left and right lens frame legs: 200mm