... quiet. 2.5V USB(cable length:1.2m) power supply, metal shell, special mesh enclosure design, all ... lower running voltage and current, power just 2.1W, energy saving. 4.Fan's life can be 25000~30000 ... ,weight(with box):390g,easy to carry. 8.Fan occupies small room, stable structure, easy to place ... comfortable. 11.USB plug and play,no external power needed,USB power adapter required for the 5V .. 1000MA 12 ...