Why does the BC21R V3 sometimes downshift to a lower output level?Updated 13 days ago

There are two reasons that this might happen. First, the light features Intelligent Overheat Protection which may be triggered after a period of use because high-powered LED lights can generate a lot of heat. When the light reaches 140°F (60°C), the overheat protection will be triggered and the light will step down to a lower output while it reduces temperature. Once the temperature is below that level you will be able to select the output again. Second, the light has a low-voltage warning. When the battery voltage drops below a preset level, the light is programmed to downshift to a lower brightness level until Low is reached. Recharge the battery to restore the higher output levels.