Choice Band

Boosts Attack, but allows one move. (Hold)

Choice Band boosts your Attack by 50%, which is a massive damage increase for physical attackers. The tradeoff is you're locked into whatever move you pick until you switch out. This means prediction matters a lot more since your opponent can take advantage of your locked move.

This item is best on Pokémon with high base Attack and strong STAB moves that are hard to switch into. The idea is to hit so hard that even resisted hits deal decent damage. Just be careful about locking into the wrong move, because that's how you lose momentum fast.