When you use the IMALENTMR90 flashlight for the first time, please remove the rechargeable battery protection between the flashlight head and the high-capacity battery pack and then tighten it as tight as possible.
Press the power switch button lightly; if MR90 cannot be turned on, quickly press the contact lock four times, and then turn on the flashlight usually. Press and hold the power switch, and when the desired brightness level is reached, release the power switch.
When turning off the flashlight, you can quickly press the power button four times to lock the flashlight.