Looks like a great way to vent a teardrop. The sleeping area of a 4' tall x 5' wide x 6.5' long equals 130 sq feet this unit exchanges 114.7 CFM. This way you could buy a roof vent with out a fan.
Specifications: 120x120x38mm, 114.7 CFM @ 2750 RPM, 45.5 dBA, 6.12w, 510 mA, 12v
only $15.00
http://www.sidewindercomputers.com/pa12ulhisp.html