Medal Box appears in 6 version groups since Generation V, a Gameplay item in the Key Items pocket
PokéAPI item 670 of 2,223, Gameplay category, Key Items pocket
Effect, in PokéAPI's words
Medal Box: “Holds medals recieved in the medal rally.”
Games
Medal Box is listed in the text of 6 version groups, first in Generation V
Game index by generation
IIIIIIIVVVIVIIVIIIIX
Named in
Black 2 and White 2X and YSun and MoonUltra Sun and Ultra MoonLet's Go Pikachu and Let's Go EeveeSword and Shield