Features: Keeps motor cooler! Make your electric motor run more efficiently by keeping it cooler! Applicable motor: Brushed 540/550 Brushless 3650/3660/3674 (motor with outer diameter of 36mm can be used!) Easy and convenient to install and remove, no need too much-time or labor, just convenient for operating. With high quality materials and exquisite workmanship, it is durable and easy to use Please check your specific model's manual for compatibility . Please feel free to contact us if you have any issue or need further assistance, we are here for you. Specifications: Material:Plastic,Metal Color:Blue,Black,Silver,Purple,Red,Gold, Note: Please allow 1mm errors due to manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package includes: 1x RC Motor Fan