Package included: 1pc 545 DC motorNote: When the voltage is 18V, the sound is soft, although it is not silent.This motor is high-speed and high-power, and is generally powered by a lithium battery.If you use a switch-regulated power supply, the current of the power supply must be at least 6A, and the larger the better.If it is too small, it will affect the power and torque of the motor. In addition, the motor with high power density is easy to generate heat. Please pay attention to the heat dissipation environment.The product will be upgraded constantly, the appearance and color may be changed,please don't mind. And take a consideration before place the order if you have requestfor color or appearance.