Main Body Highly rigid, vibration free single piece (base, column & arm) Aluminum alloy casting, with transmitted light, power supply & brightness control integrated in the base. The frame is stable, strong, big & easy to carry. Pure white body with blue on the both sides is fresh and vivid design. Optical System Infinity color corrected optical system Viewing Head 30 inclined Siedentopf binocular head, interpupillary distance: 50-75mm, 5 diopter adjustable, 360 rotatable Eyepiece Wide Field plan eyepiece 10x, FOV 20mm with diopter setting Etc.