The large lens diameters combined with an ergonomic design which provides the user with a relaxed hand position (both left and right handed) makes for maximum reading comfort and exceptional ease of use. The ultimate image quality 2 SMD LEDs positioned opposite to each other for optimum, pinpoint illumination with no shadowing Perfect illumination during battery operation LEDs provide an illumination strength up to 4000lx The AA Batteries provide upto 40 hours of illumination Automatic switch-off after 30 minutes