Range of PD adjustments：

PD of both eyes:                     

54 ~ 70mm

left or right PD:                    

27 ~ 35mm

Minimum graduated value:             

2mm

Dividing disc axial graduation：

Left dividing disc:                  

165゜ ~ 0゜ ~ 180゜

Right dividing disc:                 

45゜ ~ 180゜ ~ 60゜

graduated distance:                  

5゜

Inner diameter of lens frame：    

φ34mm

Number of lens holding：          

4 pieces

Nonparallelism：                  

≤2.5゜

Non-concentricity ：              

≤0.5mm

Displacement：                    

≤0.3mm

Range of nose rest adjustment:

Length:                               

7.5~ 11mm;   angle:0゜ ~ 20゜

Range of leg′s length adjustment：

90 ~ 120mm

Weight：                        

50g