(hex:67) is a glitch item in Pokémon Red and Blue.
Its name is sourced from the untranslated "なかよしバッヂ" (FriendBadge) string from Pokémon Red and Green, resulting in mojibake. なかよしバッヂ is also the name of the hex:67 glitch item in Japanese versions.
Using this glitch item will execute the code at FED0 in 'unusable memory', likely resulting in a freeze.