The EM 89 Digital TENS/EMS Device with heat function is a high-quality medical device that combines transcutaneous electrical nerve stimulation (TENS) and electrical muscle stimulation (EMS). These features can be used simultaneously or individually making it a versatile device for pain relief and muscle training. - 4 separately adjustable channels 8 electrodes 64 programs & 6 freely programmable programs - Safety switch-off - Rechargeable lithium-ion battery.