Safe

The Safe is a portable storage item with 40 slots to store other items. The Safe, Piggy Bank, , and Void Vault have the unique ability to be carried while they contain items. It is purchased from the Merchant for each, after Skeletron has been defeated.
It functions identically to the Piggy Bank, except that it cannot be placed on platforms or furniture surface, and can only be placed on Blocks. 
The Safe does not share Piggy Bank/Chester/Money Trough's inventory space. Items in one will not appear, or take up space, in the other.
== Differences from Chests ==
The Safe (as well as the Piggy Bank, Defender's Forge, and Void Vault) functions similarly to other storage items, but with some important differences:
* Each Safe contains the same items (when accessed by the same character), no matter where they are placed within a world.
* Purchasing multiple Safes will not give you more space, but will offer more points of access to your Safe contents, even in another world.
* The Safe can be picked up even when it contains items. This makes it a viable way to expand your character's inventory slots. It must be placed in order to add or remove items, and can be freed again with a Pickaxe.
* The Safe's contents are saved with your character data, instead of the World data. You keep its contents with you from world to world, and from server to server.
* The Safe's contents are exclusive to each player, so other players will not have access to items you store there. This makes it useful for item security on PvP servers where stealing is allowed.
* Multiple players can use the same Safe without having access to each others items. Each player will only see their own items when accessing the same Safes.
== Notes ==
* Coins stored in a Safe, Piggy Bank, Defender's Forge, or the Void Vault will not be lost in case of death, even if it is in your character's inventory at the time.
* The Safe was likely added because many players complained about running out of inventory space while looting the dungeon. This might also explain why you can only buy it after defeating Skeletron.
* Money stored in the Piggy Bank, the Safe, the Defender's Forge, and the Void Vault are added together and are available when purchasing things from NPCs. The total money stored is visible as Savings to the right of a NPC shop window.
== History ==