Gym Badges
From Pokemon Go Wiki
Introduction
Types of Badges
Bronze Gym Badge - 1 Extra Item
Silver Gym Badge - 2 Extra Item2
Gold Gym Badge - 3 Extra Item3
Official Announcement
Gym Badges: Now you’ll be able to earn Gym Badges when interacting with the many Gyms around the world. Gym Badges serve as mementos of your Pokémon GO adventures and reflect your contribution to a Gym’s success.
You’ll be able to level up your Badges by battling, giving Berries to the Pokémon in the Gym and spinning the Gym’s Photo Disc. You can earn the opportunity to receive bonus items and increased rewards from Gyms by raising the level of your Gym Badge.
