1.Eyepiece focusing range: ±5D

2.The top point dioptre measuring range: -20D~+20D

3.The minimum measuring square value: 0.01D

4.The shuttle lens measuring range: 10

5.The shuttle lens square value: 1

6.The cylinder lens axial range: 0-180°

7.The cylinder lens axial square value: 1°

8.The maximum diameter of the measured lenses: 100mm

9.The lighting(AC): 220v/110v-6v