The AVA EP10 Wireless Pen. Fine tune your swing from 2.5mm to 4.5mm Details: Material: Aluminum Motor: AVA Metal Brushless DC Motor Power Intake: 5W Motor Speed: 10500rpm Stroke: 2.5-4.5mm adjustable Needle Protrusion: 0-5mm Battery Type: 18500 Lithium-ion Run Time: 3-6 Hours with charge time of 3-4 hours Rated Capacity: 1900mAh Size: 32mm*144mm Weight: 198g(without battery) Accepts standard size cartridges. Features: Adjustable stroke from 2.5mm to 4.5mm, no limits between it. Session Timing function 18500 Lithium-ion Battery with circuit protect which protects the circuit board and incorrect battery installation. High-definition OLED screen that shows voltage, hertz, timing and power display. Click-grip needle hang adjustment. Anti-slip grip Includes: carry-case and two rechargeable batteries and the charger. Extra batteries are available to purchase here Package Includes: (1) EP10 Tattoo Machine (2) Lithium-ion rechargeable batteries (1) Battery Charger (1) Carry Case (2) Grip Tape