Feature: 1. LED DIGITAL DISPLAY: The digital screen on this power supply allows for precise voltage output display. This lightweight and compact power supply integrates seamlessly with your tattoo pen for an effortless operation. 2. 1500MAH CAPACITY BATTERY: Equipped with an integrated 1500mAh battery, it can work continuously for approximately 4‑8 hours when fully charged. For larger tattoos, alternating between 2 power supplies supports uninterrupted work. 3. WIRELESS DESIGN: Shifting from conventional power supplies that require multiple accessories to function, the tattoo power supply eliminates the need for power cords, hook lines, and foot pedals, making the tattoo artist's job easier and more convenient. 4. ADJUSTABLE VOLTAGE: With an adjustable voltage range from 4‑12V, and an accuracy of 0.1V, the power supply has been designed to cater to the varying speed requirements of tattoo artists working on different body parts. 5. RCA INTERFACE: Designed to fit most tattoo machines featuring a standard RCA interface, the power supply ensures a snug, secure connection that will not easily disconnect, facilitating a smoothness tattooing workflow. Specification: Item Type: Tattoo Power Supply Material: Aluminum alloy, electronic components Size: Approx. 37 x 64mm / 1.5 x 2.5in Battery: Built in Lithium Battery 1500mAh Output Voltage: 4-12V adjustable, adjustment accuracy 0.1V Power Interface: RCA Interface Charging Interface: USB Type C Charging Voltage: DC5V / 1A Charging Time: 3 hours Battery Life: 4-8 hours of continuous operation Boost Function: After startup, press and hold the "+, - "key for 3 seconds at the same time to turn on/off the strong start function. LED Screen Displays: current voltage + remaining power. Package List: 1 x Wireless Tattoo Power Supply1 x USB Charging Cable