Re: 12v Fans......?
Caframo is tops. And the 747 model moves more air per milliamp than any other model I've found. 400 milliamps per fan on high speed and 200 on low (but who uses low speed?). And they move more air than Scirocco or any other model. West Marine stores sometimes have a display that allows you to test the various 12V fans they sell. I ran them all and the 747 was clearly the best. One problem with them is that the suction cup provided with the fan is useless and won't stick on any surface in the boat. However when I emailed them they sent me three suction cups from older models that did work. Said they were working on a solution. West Marine sells clips that fit the fans if that is a reasonable method of making the fans portable on your boat. The fans also come with mounts for permanently mounting them that are good mounts.
The 747 is also a quiet fan.