A screenshot of where to buy Chest Keys in Treasure Aisle (TA).
This heavy brass key can be used to open a Treasure Chest. Each Treasure Chest contains either consumable items, doubloons, a ship deed, a treasure map or economy materials.
Chest Keys can be obtained by killing 40+ level NPC's or by buying them in Treasure Aisle (TA) for Burning Sea Points (BSP).