The MH12 Pro is an incredibly bright flashlight in a compact package. When used in the high setting, it can generate noticeable heat, which is a normal characteristic and not a defect. This is common among LED flashlights of similar size and performance. The only effective ways to mitigate this heat are to reduce the light output or increase the flashlight's size. We recommend using the light on the second-highest brightness setting as your primary mode and utilizing the TURBO mode sparingly to prevent excessive heat buildup.
(Please remove the paragraph below unless the buyer is asking about the runtime. Remove this sentence as well.)
As specified in the manual, the runtime testing for the TURBO setting was conducted without temperature regulation, meaning the light was allowed to run for as long as possible, regardless of how hot it became. However, in practical usage scenarios, the flashlight incorporates an overheat protection circuit that will lower the brightness if the light becomes too hot. The accumulated runtime is still accurate but not under continuous operation. This stepdown design is a standard feature in high-lumen LED lights available on the market. The change in brightness level is more noticeable in the MH12 Pro because of the brightness level indicators.