The Ipower Watch goal is to remove the unnecessary external power source and eliminates the long wire at your work station, while providing exceptional power supply output to your tattoo machine. The Ipower watch attaches to your wrist, & with a simple push of the button you can adjust your voltage to 5 different settings: 5-Volt, 6.5-Volt, 8-Volt, 9.5-Volt, & 11-Volt It also includes: (1) Open Box Ipower Black power supply (1) Micro USB to RCA Male Cord (Machine with RCA Connection) Battery Power Run Time: Cheyenne Motor or Pen: 4-5 hours Rotary Machine: 6-7 Hours (2 Hours to fully charge you IPower Watch) Special Note: Will not work long on a Coil Machine so we suggest only rotary-style machines.