From the data sheet. My suggestion would be the C1 or C2 models.
Spare mounting kit:
-
AP-220-MNT-C1: Aruba AP mount kit contains two
ceiling-grid rail adapters for flat rails
• List: $25
Optional mounting kits:
-
AP-220-MNT-C2: Aruba AP mount kit contains two
ceiling-grid rail adapters for Interlude and Silhouette
style rails list: $25
-
AP-220-MNT-W1: Aruba AP mount kit contains one basic
flat-surface wall/ceiling mount bracket
List: $75
-
AP-200-MNT-W2: Aruba AP mount kit contains one
secure flat-surface wall/ceiling mount cradle
List: $75
The W1 and W2 are way easier to use and mount and unmount the APs, whereas it is more difficult with the C1 and C2 versions (from past experience).