Intelligent Power-Off Protection: Rechargeable USB type-C charging metal engraver pen, there is a built-in overload protection chip, when the resistance is high, it automatically power off to protect it, and prolong the service life of the jewelry engraving machine Low Noise: The sound of this cordless rotary tool is very low when working, even if someone is sleeping, he or she not feel very noisy. Great for beginners and professionals to use anytime, anywhere to 3 LEVAL VISIBLE SPEED ADJUST: This electric engraving pen for all material is about 5000-18000r/min, and different speeds are used to engrave different materials. The engraving pen is and ergonomically designed to give you precise control and engraving. Smart Power-off Protection :Built-in safety protection circuit board and intelligent overload protection chip.When the working resistance is large,it automatically cut off the power to prevent from damaging the electric engraving pen., Manufacturer: Littimoon