A must for anyone who takes health seriously! - (Gauss mode) : Low frequency Magnetic field. Achieve it by pressing the mode button. (Gauss mode) (RF mode): 100MHz to 8.0GHz. The LCD back light can be turned on/off manually by pushing the 2nd button to get into the Hold mode first then toggle the 1st button to cycle through the sound-on/light-off, sound-on/ light-on, sound-off/light-off, and sound-off/light-on setup, then push the 2nd button to get out of the Hold mode.
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