TechGearLab

What makes the Treva a standout in the class of window fans is that it does not rest in the window but on the window sill. Its slender profile and option to run on 6 D-cell batteries if needed make it a good choice for personalized airflow as well as travel. This versatile fan is no slouch when it comes to moving air, either. The machine produces a wind speed of 4.5 mph at 3 feet which creates a gentle but detectable breeze as far away as 20 feet.  
While this fan's slender profile makes it easy to pack, it lacks the security of being secured in the window frame when in use. A stiff breeze from outside could potentially knock it over. Additionally, its airflow is one-directional, and there is only one blade doing the work. For anyone considering this unit for travel, keep in mind that when it's loaded up with batteries, that adds 2.5 pounds to its weight. Despite these limitations, if you need a fan for your on-the-go lifestyle or a window far from an outlet, then you can't do much better than this petite air mover. 

Portable Desktop Battery Fan Comparison