The geko® device has a constant current, square wave, asymmetrical, charge balanced pulse. The constant current refers to the output of the geko® device which is constant during the duration of the pulse. The voltage of the device will vary according to the patient’s electrical resistance in order to achieve the current output. The stimulation pulse is defined as a square wave. This means that the stimulation current rises rapidly to the required value, which is maintained for the duration of the pulse, followed by a rapid fall to zero. This creates a rectangular or square shape when measured on an oscilloscope.