These SkyMaster Pro ED binoculars for amateur astronomers include 70 mm objective lenses, BaK-4 prisms, ED Glass, and Celestron's proprietary XLT coating technology. The 70mm objective lenses have light-gathering capabilities, delivering low-light performance, even in the dimmest conditions. The Extra-Low Dispersion (ED) glass virtually eliminates chromatic aberration, also known as colour fringing, a visual defect common in binoculars, delivering edge-to-edge sharpness with colour correction and razor-sharp images. SkyMaster Pro ED's eyepieces are threaded to accept standard 1.25" astronomical eyepiece filters to deliver game-changing views. The SkyMaster Pro ED 15x70 mm's built-in tripod adapter allows the binocular to be attached to a tripod for added stability and acts as a balance rail by sliding along the centre support rod, for connecting a red-dot finderscope. Once you align it with the binocular, the red-dot finderscope will help you pinpoint your target in seconds. The polycarbonate and aluminium housing allows the binocular to be lighter weight without sacrificing its durability. The protective rubber armour is rugged and durable and can handle demanding use. The fully waterproof housing for all weather conditions provides peace of mind when unexpected weather occurs. The housing is also filled with dry nitrogen gas to prevent the internal lenses from fogging when moving between extreme temperatures or using the binocular in damp conditions. Bring distant objects into view with 15x magnification - for observing celestial objects in greater detail, searching for wildlife in the brush, or viewing a distant object on the horizon.