Click this to set it's password. Door's will check if it is correct and only let you in if it is
A key can be used to quickly enter a house through a door without having to type the password. If you're running from someone and you need to get into your house fast before they get to you, then this is your item! A key is designed just for that.
Its Bad Effects
Its easy to see that keys are helpful by letting you into your house to get away from someone or even when you're jut to lazy to enter a password, but there are still some bad side effects of keys. If you die or get knocked out someone can easily take your key and go into your base. This'll be really bad if you have something valuable there like a drill with lots of money upgraded into it.