OLLGEN 10 X 15X 20 X 25X Magnifications LED Double Eye Head Wearing Magnifying Glasses Jeweler Watch Clock Repair Magnifier Loupe with 2 LED Light 0.2-2inch Working Distance Great for Mechanical processing, jewelry appraisal, watch repair and miniature engraving etc. Too high magnification is not suitable for reading books and soldering electronics. This watch repair magnifier is not suitable for person who has limited eyesight 4 Pairs of replaceable lens included, with different magnifications (10X, 15X, 20X, 25X), can be interchanged quickly; If this magnifier is used for long time, you may use two lens barrels alternately to eliminate visual fatigue and improve work efficiency. Please NOTE - It is a useful and portable observing tool, but generally, if you wanna observe some objects, you can not use your right and left eyes to watch at the same time, just only one eye and also you'd better take turns to see and be near from the things that you want to look. NOTE: Short Focal Distance from lens to product is 0.2-2 inch (0.5-5cm), just like the principle of microscope. For better to observe, the distance is very close. Please check it out it really suitable for before you purchased. Eye patches can rotate 180 degrees upwards and downwards on the bracket . It's not required to take down the whole lens bracket when the magnifier is not used temporarily and you can reuse it conveniently NOTE: This is not stereo vision!  This upgraded product adopts two AAA batteries which greatly increase battery capacity and its battery duration is twenty hours longer than that of old-style product.Eye patches can move 5mm leftwards and right wards on the bracket . Face width and distance between left/right eyeballs can be adjusted to adapt to the central position of eye patches between both eye.