Brushless dc fans come in 13 sizes from 25-172 mm, with thicknesses from 10-51 mm. Offered with choice of 7 housing types, they operate at speeds from 1,600-13,000 rpm with airflow capabilities from 1.49 to upwards of 121 cfm. DC blowers deliver concentrated spot-cooling at noise levels down to 21.61 dB. They are available in 5, 8, 9, and 12 cm sizes with speeds from 1,600-5,000 rpm and flow rates to 42 cfm.