Applications:1. You can install the wheels to directly remote control car.2. Use double sides coated with glue to fix this reducer to the small wooden plastic plate (or carton), then install two small 2.5mm diameter wheels on the shafts, you can make the manual car rear wheel system.3. It can also be used to create other technological models that need to slow down the power plant, such as mini tanks, pulley drives, and even microstrip models. Specifications: Random color supply (if you buy more than one product, the colors may be different or the same) Working Voltage: 3-6V Rotation Speed: when the voltage is 3V: 700rpm, 90ma; When the voltage is 6V: 1300rpm, 120m Shaft diameter: 2.5mm Total shaft length: 75mm, each side is about 28mm Size: 45x22x29mm Quantity: 1 PcNote: Please allow 1-3mm error due to manual measurement. Pls make sure you do not mind before you make a bid, due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!No Retail Package Content:1 x Gear Motor