Full Item Description
It appears to be a normal key with the exception of tiny runes scribed down the one side of it.
History? Isn’t it obvious? A mage somewhere got tired of losing his keys and thusly enchanted his to return to him whenever he lost them. Seems the idea has caught on.
The owner of the key simply has to speak a command word while holding his or her open palm and it will appear there. The key will not do this if broken, on a different plane, made incorporeal or altered in such a way that the ruins are distorted or destroyed.