Do you use a tattoo machine? Do the wires that power the machine always get in the way?
If you answered both of these questions with yes then this is the solution for you!
The battery pack has a digital display that shows shows your information while you work.
It shows the voltage you have set it too, the battery life that is left and how long you have been working for.

This battery pack can easily be turned on and off through a power button, and increase/decrease the voltage through the arrow buttons. 
These battery packs are not compatible with machines that use a RCA or Jack Plug (Cheyenne) connection
Included in the box:
One Wireless Battery
USB Charging Cable
Technical Specifications:
Use the power button to switch it on and off
Battery life: 5 ~ 8 hours of tattooing, depending on the use.
Charging time: 120 minutes
Operating voltage: 4 ~ 11V
Capacity: 2000mAh
Voltage adjustment resolution: 0.1V
DC Connection    and  RCA connction
Weight: 69 grams