Feature:   1. [40000RPM Adjustable] Electric nail polishing machine offers a speed range from 0& 8209;40000 RPM, allowing you the flexibility to choose the perfect speed to suit your needs.     2. [Quiet Operation] Designed with a high speed, low vibration, and low noise motor,nail drill machine ensures that you can work in peace without disrupting others.     3. [Touch LCD Screen] With its large touch LCD screen display, which combined button and display, you can easily monitor your RPM data in real time and select rotation direction on it.     4. [Convenient Power Source] Electric nail polishing Machine is powered via a USB interface, allowing it to use a variety of power sources, including plug sockets, computers, and power banks.     5. [Portable Design] Nail polishing machine is designed to be compact and lightweight, making it easy to carry around and use anywhere, without taking up too much space.             Specification:               Item Type: Electric Nail Polishing Machine  Material: ABS  Rotational Speed: 0-40000RPM                       Package List:       1 x Grinding Pen       1 x Host Connector       1 x Grinding Head       1 x Storage Box       1 x Instruction Manual               Note:           1. When switching the direction of rotation, the speed should be set to 0 or paused first. The machine needs 2 seconds to buffer during the switching process.              2. When replacing the polishing head, the machine must be turned off and cannot be operated when turned on. If the polishing head is not locked, the handle will not rotate.                    How to use:       1. The tip of the polishing pen has an elastic rotating head, which can clamp the polishing head at the bottom.           2. Speed control line connector.           3. USB interface.           4. Speed display: 00& 8209;40RPM, representing 0& 8209;40000  digits.           5. Press and hold the "+" button to increase the speed; press the "& 8209;" button to decrease the speed.           6. Press the "II" button for one second to pause, press again to resume.           7. Forward and reverse: when the machine is turned on, it rotates in the forward direction "F". Press the button to switch to the reverse direction "R", press again to switch back to the forward direction.           8. The connection port for the polishing pen to connect to the main body.