Specifications:
Spherical lens power range: +16.75D~-19.00D, the minimum power is 0.25D or 0.12D (when using +0.12D auxiliary lens or selecting ±0.12D lens)
Astigmatism power range: 0 to -6.00D, minimum reading is 0.25D or 0.12D (when using the attached lens) 0 to -8.00D (when using the attached lens -2.00D)
Astigmatism axis dial: 0 to 180° in 5° intervals
Cross cylinder: exchange type (used simultaneously with astigmatism axis) ±0.25D, ±0.50D is also optional
Rotating prism: 1D per interval, 0 to 20D
Interpupillary distance adjustment: 48mm to 80mm, each interval is 1mm (the same for left and right)
Front desk adjustment: 16mm forward and backward
Focus: Within 400mm from the tip of the cornea (2mm to the left and right sides), the axis of the optical lens is in a straight line. Can focus within pupil distance from 57mm to 80mm
Method for testing corneal distance: Starting from the standard platform, use a scale to measure the front 2mm and the back 5mm
Effective range of field of view: 19mm
Volume: 323X315X85mm
Weight: about 5kg

Packing list:
1 x Tester Phoropter