Cordless Power Supply Rotary Tattoo Pen Professional Aluminum Alloy Motor Tattoo Pen with RCA Converter Item Type: Cordless Power Supply Rotary Tattoo Pen Material: Aluminum Alloy Needle Stroke: Approx. 3mm / 0.1in System Voltage: 5-12V, Adjustment Accuracy: 0.5V Common Working Voltage: 5-10V Speed: 12V 10800r/m Battery: Built In Lithium Battery 1800mAh Motor: Coreless Motor Applicable Needle: Universal tattoo cartridge needle Product Size: Cordless Pen Length: Approx. 14cm / 5.5in, Wired Pen Length: Approx. 10.8cm / 4.3in Chargers for Cordless Power Supply: 5V/1A, 5V/1.5A, 5V/3A. Do not use 9V/1.5A, 9V/2A, 12V/1.5A, 12V/2A and other fast chargers to avoid damage to the battery. Cordless Power Supply Charging Time: 2 hours, 5-8 hours of battery life after full charge