Easy to use: Dr. Pen A6S can be used wireless (with rechargeable batteries), or with the cord, both included.<br />Adjustable Speed and Depth: The additional feature of 5 different speed levels is now getting popular. Using its unique knob design, you can adjust the depth of the cartridges<br />Dr.pen Ultima A6S Pen: Newest and improved model of most popular Dr.pen Ultima A6 Microneedling Pen<br />Important:Before turning on the pen, make sure to remove the white cover on the top of the cartridge. Use each cartridge only ONCE. Always dispose of cartridges after use; they are NOT reusable. Repeated use of a cartridge may result in skin irritation and other adverse side effects. ">