Ueasy Compact Scalable Monocular 10x to 90x Zoom 25mm Pocket Size Mini Hd Telescope Monocular with Tripod Bak4 prism, multi coated optics guarantee superior light transmission and brightness. 10x to 90x zoom; 25mm objective lens. Stretch length scope: 5 inch-7.5 inch. Long eyerelief eyepiece with twist-type retractable eyecup assembly Dual Focus-Rotate the focus & Stretch focus. Fits for Bird Watching, hunting, outdoor sports, vocal concert, athletic meeting and so on.