There are two problems with your advice. Similar fans have a three times higher power consumption and will do 550cfm.The second problem is that google only spits out similar ebay auctions with the same description.Also the data on ebay could be wrong. Here is a pdf with a fan of similar size. I guess i shouldn't have bothered you with this question. I will soon find out how powerful they really are when they arrive at my doorstep.With only 5$ a fan you really can't go wrong.
pdf doc