The Rival Perses is barely even out yet and people are itching to shove some LiPos into one. When the Perses' stock battery isn't installed the battery tray is wide open. This cover inserts into the Perses and uses the same latching mechanism as the included battery.
I've also included a small cutout in the battery cover to avoid damaging the Perses' stock battery contacts. Just in case any of you ever want to unmod your blaster and convert from LiPo to stock battery pack in the future.