Ambition tattoo power supply work with the majority of RCA rotary tattoo pen machines and assist tattoo artists enjoy portability and ease of use. Specification: Material: Aluminium alloy and high quality insulating plastic. Battery Capacity: 2000mAh Charging Time: About 1.5-2 hours Operation Time: Under normal 8V voltage, the battery voltage stable state can last 6-7 hours,long time working the voltage is stable Output Voltage: 4-12V LED Display Content: Output voltage range + battery usage+working time Charging Method: Type-C Interface: RCA interface Size: Approx. 73 x 32mm How to Use: Power ON/OFF: Long press "O" key for 3 seconds（jump start function mode is off） Power ON/OFF: Double press "O" key for short（jump start function mode is on） 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. LCD display shows 4-12V, each adjustment ±0.1V.