16X52 Day&Night Adjustable Focal Length Porro Prism Telescope Monocular Multi-coated optics upgraded version of the green AR. Twist-up eyecup. Single hand operation. Powerful, ultra-compact and ultra-lightweight. Rubber Armored for rugged field use center focusing mechanism for quick,easy focusing. This monocular offers an 16x magnification and a 52mm objective diameter The larger the objective lens, the more light that enters the binocular, and the brighter the image. Magnification: 16x. Objective lens dia: 52mm. Prism:Roof. Prism Glass: BAK4. Field of View: 66M/ 8000M Eye relief:18mm. Exit Pupil:5.2mm. Coating FMC upgrade broadband green Lens. Size:145 x 52 mm. Color:Black. Water/Fog Proof: basic ( Not supported while Diving)