You'll need to download the model file and 3D print the part. To download the model file and get more information, please visit here. In the Box: Motherboard*1， Motor*1， Battery box*1， M2.5x7 <30， Gear*1， Screwdriver*1 Note: 1. It is recommended to use indoors at room temperature. 2. The product contains small parts. Take precautions to prevent children from inhaling or swallowing them.