Feature: 1. 4‑11V Adjustable Voltage: The adjustment voltage accuracy is 0.1V, which can meet the speed requirements of tattoo artists to operate on different parts. 2. Display Screen Design: The current voltage, battery remaining capacity and operation time can be clearly observed, which is convenient for the tattoo artist to observe and operate. 3. Standard RCA Interface: Suitable for most tattoo machines with RCA interface, closed tightly and not easy to fall off. The power cord, clip cord, and foot pedal are omitted, convenient for use. 4. Long Endurance: Built in 1700mAh high capacity battery, when fully charged, it can work continuously for 5‑8 hours, suitable for tattoo salon. 5. Aluminum Alloy Material: Cordless tattoo power supply adopts aluminum alloy material, safe and eco friendly, anti rust and no deformation, durable for use. Specification: Item Type: Tattoo Power Supply Material: Aluminum Alloy, Electronic Components Interface: RCA Interface Battery: Built in lithium battery 1700mAh Power Supply Host Size: Approx. 70 x 33 x 33mm / 2.8 x 1.3 x 1.3in Input: DC5V 1A Output: 4-11V Output Voltage Adjustment Accuracy: 0.1V, long press for quick adjustment Charging Time: 3 hours (it is forbidden to charge with a charger higher than 5V) Use Time: Can be used for 5-8 hours. Package List: 1 x Cordless Tattoo Power Supply1 x USB Charging Cable