Features Automatically Cut Off: Our engraving pen is rechargeable and come with a USB cable. When the working resistance is too large, engraving pen will automatically cut off the power supply to prevent damage. Overload Protection: Built in safety protection circuit board of this small grinder pen and intelligent overload protection chip. And very safe to use. 3 Speed: Working power is 10W, 3 speed for this pen type small engraver can be adjusted in the range of 10000, 15000, 20000 r/min, suitable for different materials. Low Noise and Light Weight: Don't worry about interrupting your family's rest. The our etcher engraving pen is light and small. You can take it with you. The noise is low while working. Aluminum Frame: High performance motor and the lightweight aluminum frame and ergonomic grip, this engraver pen provide you with great finger tip control. Specification: Item Type: Small Engraving Pen Material: Aluminum Alloy Battery: 3.7V Lithium Battery x 1, Battery Capacity 380mAh (Shipped With Internal Battery) Speed: 10000rpm (Low Speed), 15000rpm (Medium Speed), 20000rpm (High Speed) Power: 10W Package List:1 x Engraving Pen 2 x Engraving Bit  1 x USB Cable Package List 1 x Engraving Pen 2 x Engraving Bit 1 x USB Cable