The ModuVents™ in the Define R5 are placed in a specific order. There are two FRONT ModuVents™ and one REAR ModuVent™. Please note the REAR ModuVent™ has a slightly different design than the FRONT ones to help distinguish them.
If you want to remove the ModuVents™, the REAR ModuVent™ needs to be removed first.
There are two hooks and two latches on each ModuVents™. The REAR ModuVent™ hooks are pointing towards the rear of the case and the FRONT ModuVent™ hooks are pointing towards the FRONT of the case.
The latch needs to be pushed like this (see picture below) for an easy removal. Push the inner part of the latch (the part closest to the center of the top panel) outwards from the case towards where the side panels would be located.
To snap the ModuVents™ back, you must start with the front one, by simply sliding the hooks into place first and then gently push the latches in place. This should be an easy snap in - no force required.