A Raid Pass is a free item that allows the player to participate in Raid Battles once a day. Upon entering a raid battle, the pass is used up and can be earned back by spinning a gym the next day. These items do not stack, meaning only one can be held at a time.
Raid Passs are used to join Raid Battles featured at a Gym. These passes have one use only, and can be re-obtained daily by visiting a Gym and spinning the PhotoDisk.