[Smart 0ver-load Protection & Pure Metallic Hand Feeling]: Built-in overload protection chip, when the resistance is too high, the cordless engraver pen will automatically power off to prevent machine damage and extend the lifespan. Made of solid metal, the outer metal wrap gives you a better metallic touch instead of a cheap plastic texture, and it will never discolor or peel off during the use. [3 Level Speed Adjustable & 2-Way Rotating]: The cordless electric engraving pen's Rotational Speed up to 20000r/min, and buile-in 3 different speeds (Short press) to engrave different materials. The engraving pen is lightweight and ergonomically designed to give you precise control and engraving. [Low Noise, Perfect for Beginners]: The cordless rotary engraving tool is very lightweight and portable during the short journey. The working sound is very low, even quiet lol, it will never make the interrupt even the others in a room. (The Smart Power-Off Protection will protect the beginners for safe use. We suggest this tool for adults only.)