1. Objective Zoom: 0.7X-4.5X2. Zoom Ratio: 1:6.43. Eyepiece: WF10X/20mm (WF15X/15mm; WF20X/10mm; 25X/8mm for option)4. Auxiliary Objective: 0.5X/165mm; 2.0X/30mm5. Interpupillary Distance: 54-76mm6. Diopter Adjustment: ±5