Figure 1From: Validation, reproducibility and safety of trans dermal electrical stimulation in chronic pain patients and healthy volunteers Transdermal Electric Pain Stimulator (HV-1). A) Stimulator without enclosure. Electrostatic-like discharges are visible between skin and the electrodes, B) Scheme of the stimulation head, C) Stimulator is simply attached to the forearm by Velcro strap.Back to article page