The optional heads are used for different treatment depths. Use the 2.0mm head for more superficial areas, such as fine lines and thinner facial skin. Use the 3.0mm head for general facial tightening. Use the 4.5mm head for deeper lifting areas, such as the cheeks, jawline, and lower face. Please always apply enough conductive gel, start at the lowest intensity, and keep the probe moving slowly upward. Do not use directly on the eyelids, eyeballs, open wounds, inflamed acne, or areas with implants or fillers.