Designed for custom DIY projects that require a controllable cooling and ventilation solution * Features two heavy-duty aluminum fans which can be speed controlled * Each Fan | Size: 120 x 120 x 25 mm ( 4.7 x 4.7 x 1-Inch ) | Airflow: 20 to 69 CFM | Noise: 25 to 38 dBA | Speed: 0, 700 to 2450 RPM | Bearings: Dual Ball * Contents: (2) 120mm aluminum AC fan, (4) metal guards, (2) 2-Inch screw mounting set, (1) dual speed control unit * May not be suitable for noise sensitive applications such as amplifiers and AV cabinets