Pokémon Storage Upgrade

A Pokémon Storage Upgrade is a purchasable device that increase a Trainer's maximum Pokémon storage capacity.

Details
It can be purchased from the Shop for. Purchasing them multiple times, increases storage capacity by 50 Pokémon—up to a maximum possible size of 1,000.

In-game description
Increases the max number of Pokémon you can carry by 50.