Please check it before purchase:this link has rechargeable version and battery version(battery not include):
Features of Product: According to the design of human engineering,this aesthetic and sicentific product is in accordance with the neck curve. Two 7#battery for power supply and it is safe and reliable for use. Adopting newest 3D smart fit technology,you can easily adjust electrode according to your neck curve,If using the external connection,you will feel more comfortable. There are three automatic packaging physiotherapy modes and three manual physiotherapy modes.You can choose any modes in accordance with your requirements.It has a wider suitable range of the crowd. This product has LED indicator and an easy operation systen,which is clear to use and more humanistic. Rechargeable version Power supply:built in 3.7v rechargeable battery Battey version Power supply:3VDC30mA(2 knots battery)(battery not include) Equipment safety category:BF type applicatiob Part Pulse frequency:0hz-1000hz Pulse width:20us-400us Relative temperature:less than 80% Atmospheric pressure:86kPa-106kP Note:Do not use it when recharging! Packing :Please note that the link has battery version and chargeable version, and battery not include. Please note that the price is different and the quantity of hydrogel patch is also different.Please contact our customer service if you have any questions.