Great optics for the money. - Holosun Paralow HS515CU Micro Red Dot Sight with Solar Power

These optics are awesome for the money. Batteries last several years and they hold zero. The negative review claiming two units would not utilize the battery and only solar probably decided to skip over the menu and did not realize these have manual mode and auto mode. The auto mode is very dim and almost not visible unless unless the solar panel is getting light. If you follow the instructions it will tell you how to put it in manual mode to put brightness as high as you need it.