Do I need an 18 db crossover module, or a 24 db crossover module?

We have many products that have PFM modules and/or crossover modules that the user can replace to customize their setup.

ALL of the PFM(Progammable frequency match) filters are 18db crossovers.

The 2XS has an 18 db crossover

The Three.2 and the EQX have a 24 db crossover.

The 6XS has a mix of both.  Click here for a diagram detailing which are which.