We are not licensed medical professionals, so we are unable to comment or give any advice on this. Legally, we can only describe what the Longevity Zapper is.
It is a device that generates positive and negative offset square waves. A square wave is a kind of non-sinusoidal waveform, most typically encountered in electronics and signal processing. An ideal square wave alternates regularly and instantaneously between two levels.
We recommend you research the difference between positive and negative offset square wave forms.