Since it has no siding, it will just hang off the edge a bit on each end, nothing drastic.
As long as those fans are directly located under a vent port on your laptop, it shoud do fine. However, if your laptop has side vents, and no kind of cooling underneath...the only thing it will do to help cooling is raise it up a little. Most coolers with fans are designed to either suck air away from a bottom exhaust prot, or force air into a bottom intake port.
