Help choosing fans

[RobTi]

Hi so not really a pc question but thought I would get a better answer than the home cinema section as I searched in there, so looking for a few fans that will be fixed to an av cabinet just to circulate cool air round and then out again and also a fan that will sit on top of my av receiver to draw air up through it, any help ?
Thanks

 

[RobTi]

Thanks everyone for the help, was telling my son i had asked and he reminded me that i had 2 140mm and 120mm from my case that i had changed all the fans so these were spare. So fitted the 2 140mm on top of the avr pulling air up and then 4 120mm to get air into the cabinets and through and out the other side, all controlled by a cheap thermostat control, so rough atm but will tidy it all up later and get the controller on view to monitor temps