Machine Specifications: Motor Speed: 7.5v/10000Rpm Stroke length: 3.6mm Weight:150g Working Voltage: 5-8v Custom coreless motor 7.5v/10000rpm, same with Mast Tour Pro tattoo machine Tested lots of times then make this special custom coreless motor for this macine operating mechanism Battery Specifications: Weight: 70g Diameter: 32mm Length: 73mm Battery Capacity: 1800mAh Working Voltage: 4-12V