Lock Capsule appears in 8 version groups since Generation IV, an Unused item in the Key Items pocket
PokéAPI item 513 of 2,223, Unused category, Key Items pocket
Effect, in PokéAPI's words
Lock Capsule: “Contains TM95 (Snarl).”
Does nothing.
Games
Lock Capsule is listed in the text of 8 version groups, first in Generation IV
Game index by generation
IIIIIIIVVVIVIIVIIIIX
Named in
HeartGold and SoulSilverBlack and WhiteBlack 2 and White 2X and YSun and MoonUltra Sun and Ultra MoonLet's Go Pikachu and Let's Go EeveeSword and Shield