The EMS device is charged via a USB interface. 
This enables you to use the EMS device anytime and anywhere, with 3 connections simultaneously charge.
Efficient training: A 20min training with the EMS device corresponds to the stimulated muscle groups, such as a 2000m run, 200 sit-ups and 60min swimming. 
For your health, our abdominal muscle trainer switches off automatically after 20 minutes according to human needs. 
Automatic shutdown in 30 seconds if there is no skin contact.
Thank you!