The AERLANG portable back massage gun features a professional heated massage head (with a separate on/off switch) that uses heat to accelerate muscle relaxation, allowing you to massage sensitive areas from gentle to deep penetration. Six massage heads are also available, offering a variety of muscle group options. The muscle massage gun is easy to operate. It features 20 adjustable speeds. The heated head with three adjustable temperature settings (up to 131°F) for targeted and effective relief of muscle pain and tension.