Lazy Daze Owners' Group

I've used four 12 V fans: the Fan-Tastic "Endless Breeze," the Caframo "Ultimate" that Don mentioned, the Hella Turbo, and SVHotwire's "Port Fan." Here's a brief comparison:

Endless Breeze - 14" white box fan (with included stubby feet) moves a lot of air quietly, but uses a fair amount of power (one to three amps) compared to the others, which all use less than half an amp. No way is provided to mount it under a cabinet--my preferred location for a fan in an RV--but see my website for plans for a gimbaled bracket.

Caframo "Ultimate" - White 7" fan on tilt/swivel mount. No blade guard--plastic blades are supposed to be non-injuring, but believe me, they hurt if you get your hand in the way! And you will get your hand in the way, because the off/low/high switch is mounted on the back of the fan, so you must reach around the spinning blades to get to the switch! Dumb design. Otherwise it's a decent fan, but not my favorite. Mounts to cabinet underside, but also available in a model with a wire stand.

Hella Turbo - Off-white 5.5" fan with gimbaled housing with round blade guard, large off/low/high speed control knob mounted on front where it's very easy to get to. Mounts under cabinet (no stand available, although you could make one). Fairly quiet, draws less than half an amp. My favorite of the four. One caveat: friends tell me these fans are prone to bearing failure (rattling) after a couple of years. I'm willing to take the risk.

SVHotwire "Port Fan" - Black square 4" fan with black gimbal mount. This is a modified computer fan, but not a cheapie--it has a high-quality brushless motor that supposedly will outlast fans such as the Caframo and Hella. Under-cabinet mount, like the other three small fans mentioned here. Has two speeds and very low power consumption (less than half an amp), but while not noisy, its pitch is higher than the Caframo or Hella fans, and I find the sound a bit more annoying.

Summary: the Endless Breeze is the largest and most power-hungry of the four, but then it moves the most air. The Hella Turbo is small, well-designed (blade guard, front-mounted speed knob), and has very low power consumption, but may not be as long-lived. The Caframo would be a good fan if not for its lack of a blade guard and its backside-mounted power switch. The SVHotwire Port Fan uses the least power of the four, and should have a very long lifespan, but its higher-pitched sound can be annoying... and it's black, which isn't my preference.

I like the idea of a controller.
I did find these. What do you think?
6V 12V 2A 30W DC Motor Speed Controller PWM Adjustable Variable Driver...

P.S.--Turns out Ryobi now offers a One+ cordless router. But it looks as if it would be top-heavy with the battery (not shown in Amazon's product photos) up there. I still love my lightweight yet powerful DeWalt. :-)

I have the O2Cool battery operated fan and for my money it's not worth my money because it does not move enough air. 

"What you don't know is its power draw and that's a big deal to those of us living inside battery constraints. I have measured it and I'll share:
low: 15 Watts or 1.25 amps @ 12 VDC
medium: 27 Watts or 2.25 amps
high: 35 Watts or close to 3 amps"