Tattoo Power Supply - Ambition G4 Professional Portable RCA Wireless Tattoo 1950mAh Lithium Battery Supply with LCD Digital Display for Rotary Tattoo Pen Machine Gun Material : space aluminium alloy + high quality insulating plastic Connector : RCA Charging time : 2 hours Operation time : After fully charged, this battery can work continuously for 6-8 hours, or even longer. It depends on personal usage and tattoo machine. Output fixed current : 2A Working voltage : 3.7V Charging voltage : DC 5V±0.5V 1000mAh Output voltage : 5-12V Adjustment interval : ±0.5V LCD display content : output voltage range + battery usage + timer Instructions for use: - Power ON/OFF: Long press "O" key for 3 seconds - Output pause / resume: Short press "O" key to pause the output, and short press it again to resume the output(the resume voltage is the working voltage before the pause). - Adjust output voltage: Press the "+" or"-" key to adjust output voltage. The voltage can be adjusted through button (+) and (-) respectively with the voltage of 0.5V on each press. - Working time: The working time can be accurate to minutes. When the power is turned off, the time will be cleared. When the output is paused, it will also stop counting. Power: The LCD display will show the remaining power, and the full power will display 4 divisions. Fast charging through the matching fast-charging USB data cable can usually be fully charged in 1.5-2 hours. Please pay attention to the change of power at any time to prevent sudden power loss from affecting your tattooing work.