CFL 12"x13"x24" exhaust question

Hiya people Ive been reshearching these forums for days but I have yet to find and good ideas/pictures for a ligh proof exhaust for my flower room.

I'll be running 3 42 ww CFL and need some advice on how to exhaust.

Thanks for any help you can give me

CPU fans are dirt cheap and easy to find. I think a 4 inch cpu fan would do the size of your box well. As for light escaping, I suggest going to home dePot and getting baffled vent cover.