GM-171 Binocular Greenough zoom optical system Binocular head, 45º inclined, 360º rotating Widefield adjustable eyepieces N-WF10X/23mm 6.7:1 Zoom ratio, WD=110mm Objective magnification range: 0.75X-5X Specialised gemmology tilting base, 0º to 45º tilting range: 360º rotary base Coarse focusing system with tension adjustment 6V/30W halogen brightfield/darkfield illumination with intensity control Flexible gooseneck 7W fluorescent incident illumination Main supply 220V-240V (CE) Wire gem holder Aluminium carrying case and dust cover