The Biotronix TDCS Brain Stimulator Device is a compact 4-in-1 neuromodulation system integrating tDCS, tACS, tPCS, and tVNS technologies in a single device. With precisely controlled stimulation from 0.1–4.5 mA, multiple waveform options, and both cranial and auricular electrode configurations, it provides flexible, non-invasive brain and nerve stimulation for professional neurorehabilitation applications. Its lightweight, rechargeable design makes it suitable for clinical, research, and supervised home-use environments.