The personal chest used to be called, "Electric Chest" that could lock with the use of electricity. Now it is called the Personal Chest and doesn't need electricity. You can still lock it, and set it to "trusted".
The chest can be placed down and used as a regular, normal chest. This chest has the storage of a double-chest but the space of one chest. If you right click the air, your chest's storage will open up. If used with a Logistical Transporter, items can be piped in and out of the chest.