If held by a Slowbro (or is present in the player's Bag)PE, allows it to Mega Evolve into Mega Slowbro if its Trainer has a Key Stone. Each Trainer can only Mega Evolve one Pokémon per battle.
Unaffected by item negating effects (such as Embargo and Klutz). Item manipulating effects (such as Trick and Fling) cannot give Slowbro a Slowbronite or remove a Slowbronite from Slowbro.
![](https://s2.save4k.ru/pic/wJQnfn8vFwY/mqdefault.jpg)