this was made to work with a 5v 24mm fan and on any printrbot version. this is a 2 part print with the main mount and the directing nozzle. I made it this way so i could change the direction and speed of the air easily without needing to re-print the whole part. I also didn't want all of the air flow as in other fan mounts, because it actually caused many prints to shrink and pop off in the middle of long runs. Go right ahead and change this and use it as you want, it is likely not a fan size anyone is likely to use, but the nozzle design is something that could be useful.
I plan to print this as soon as i get another aluminum bed for my 6x8 mod,(first one i got wasn't flat at all) and will be able to update, sorry not much to look at atm.
I also am going to eventually make the nozzle easier to print, but for now it will need internal support, sorry about that.