Features: Made of the highest quality material, with high strength and hardness, strong construction, durable to use. Excellent build quality, smooth metal surface with no visible scratches. High torque, high power, stable rotation speed. Compact size and light weight, low noise and stable performance. The voltage range is 3-12V, about 7,4V is recommended, 12V rotation speed is too high. Specification: Engine model: engine 395 Voltage: 3-12V (recommended about 7,4V, 12V rotation speed is too high) Current without load: 3,7 V 400 mA, 6 V 440 mA, 7,4 V 460 mA, 12 V, 650 mA Speed: 3,7 V about 10000 revolutions 7,4 V 20 000 revolutions List of packages: Engine 1x395 Note: The starting current must be greater than 2A. Please use a lithium battery or power adapter larger than 2A. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.