115V AC Cooling Fan. 127mm x 38mm HS 115V AC Cooltron High Speed Fan Case Size: 127 x 127 x 38 mm ( 5 x 5 x 1.5 in ) Airflow: 123 CFM | Noise: 50 dBA | Speed: 3100 RPM | Power: 20 W | Bearings: Dual Ball High Airflow: This model is designed to maximize airflow and can be too loud for some applications Smaller models with a lower speed are also available, links can be found in the product description.