Super high-speed fan with a monster performance. Extremely high airflow. Recommended power source - 3s lipo. The 3S adaptor is included with an on/off switch.Specifications:Dimensions: 80x40x28mmBearing: Ball BearingOperating: Voltage 6V - 11.1VMotor mount sold separately:36-38 Dia. Motor: Part# PHMount0140-42 Dia. Motor: Part# PHMount0247-49 Dia. Motor: Part# PHMount0356-58 Dia. Motor: Part# PHMount04