Tens Unit Machine Device 24 Massage Modes Newest Model Muscle Stimulator for Lower Back Neck Shoulder Pain Relief Massager Comes With 10 Pads [5 Pairs]FEATURES : Multiple preprogrammed 24 different massage modes. Adjustable 20 to 60 minutes timer by using " T " button. Rechargeable internal lithium battery. Up to 20 hours continues use. MedTens Tens Machine can be connected to wall charger, power bank or laptop USB port to charge. Battery level indicator remind you charge timely. TENS EMS Combo : You can use either Tens modes or EMS modes or you can use the combination of TENS and EMS modes. Multi