The Slydart Silver Bullet Motorized Dart Sharpener is a self container dart sharpening device. To operate, unscrew the bottom cap, remove round clear plastic sheet and replace cap, simply press the Slydart logo to activate, insert the dart tip in either hole on unit top. Please note it is important that little pressure is required and only a few seconds is required to sharpen in order to debur the dart tip. The unit is designed to stop operating if too much force is applied while sharpening. Battery included.