Cooling fan for tube amp?


I added the Iso-Acoustic footers under my tube amp and see that I have about 2" of clearance and wonder if I someone could suggest a small fan that I could mount on my open wood audio rack to dissipate the heat from the KT88 and 6SN7 tubes in the amp?   If this has been covered before, please point me to the proper links.  Thanks.  
whitestix
Great suggestions, but I need a fan to be mounted on the back of the rack to cool the amp.  Just a wee bit of air movement will suffice. 
whitestix
... I need a fan to be mounted on the back of the rack ...
@whitestix why does the fan need to be mounted at the back of the rack? Your 2 inches of vertical clearance will accommodate an AC Infinity unit, which can then exhaust to the back or front of the rack.
Thanks all for the heads up on AC infinity cooling.
Their smallest fan at medium speed brought my UltraCap LPS 1.2 from 126° to 95° with silence @ 3 feet.