Technical Data

Measurement range:: 3-38 mm, 9-99 D
Accuracy: +/- 0,1 D
Reproducibility: +/- 0,1 D
No. of rings: 22
Working distance: 80 mm
No. of test points: 22.000
Dimensions H x D x W: 42 x 26 x 17 cm 
Weight (measuring unit): 2,3 kg 

According to Medical Device 
Directive 93/42/EEC 

Minimum PC Requirements:

Pentium 233 PC, Windows 95 or above, 16 MB RAM, VGA 800x600 graphic card at least 256 colors.