Three large fans, ball bearing construction for long life  Two Turn Off Modes, instant turn off or 10 minute delayed turn off  Three user-selectable fan speeds  High air flow, greater than 90 cubic feet / minute at max speed  Three auto turn on modes, 12 Volt DC trigger, 120V AC or front panel button  Auto turn on mode disables front panel power button  Extra-quiet design, less than 33 dB noise  Switchable 115v / 230v operation  1U half-rack space chassis  (W x D x H): 9 ½" x 9" x 2 ¼" / 1 ¾" without feet  (W X D x H): 242mm x 229mm x 57.5mm / 44.5mm w/o feet  Parasound 2 year parts, 2 years labor warranty    (For USA and Canada purchases only)