There is Electro-Acupuncture and Electro-Stimulation.
Electro-Acupuncture is when an electric signal is applied direct to the Acupuncture needle which has been inserted into the patient. Typically Electro-Acupuncture is used for muscular skeletal issues for example the lower back area, or elbow/knee joint. Firstly needles are inserted into the patient and then electrical wires are attached to the needles from the device. The signal to the patient is then controlled by the practitioner from the device. The device used is a portable unit about the size of a hard back book
Electro-Stimulation is where no needles are inserted. Instead an electrical signal is usually applied using a probe which is about the size of a ball point pen, or small pads similar to a TENS machine. Electro-Stimulation is often the preferred choice for patients who are perhaps anxious regarding needles.