DR-HO'S Pain Therapy System with Four TENS Pad is a professional TENS (Transcutaneous electrical nerve stimulation) device used by Chiropractors and physiotherapists. It is scientifically proven to relieve pain, reduce muscle tension and spasms, increase tissue oxygenation, and improve circulation. It includes: Travel bag, instructional DVD and manual, travel foot therapy pads, sixteen small massage pads, four large massage pads, pain therapy back relief belt, magic heat pad. Precautions: Please consult instructional manual for complete warnings and instructions before using this device, it should not be used by patients with conditions like pacemakers/defibrillators/extreme cardiac irregularities, metal implants or electronic auxiliary devices, abnormal high blood pressure, a tendency toward internal bleeding, epilepsy, pregnant women, any questions or concerns.