Long press the power button to power ON/OFF the tattoo machine. Quickly double press the power button to activate start-up function. When you going to start the battery and lightning lcon on display will appear. Press power button one time to start/pause the battery,Pedal icon will indicate the working. Big battery catacity 1800mAh, can use for 10 hours. Specifications: Weight: 70g Diameter: 32mm Length: 73mm Battery Capacity: 1800mAh Working Voltage: 4-12V