Ok, I think we need to clear up a few things, the REMOTE key is just a key blade with a big plastic shell over it, the shell holds the TRANSMITTER and the battery for the transmitter.
The transmitter is NOT the same thing as the transponder.
The VALET key is gray, it allows a valet to lock/unlock the car and drive it to be parked but it does not work on the glove box, so you can lock stuff in there and the valet person can't get your stuff.
The MASTER key is the key that is synced to the truck at the factory, it does everything, you must have this key to program a spare.
The key with the remote is also the master key, the valet key is NOT a master key.
All of these keys have a transponder chip in them, that is a little magnetic computer chip, that does NOT require power. When you insert your key into the ignition the transponder "talks" to the security system and lets it know that the key is valid and it is ok to start the engine. The receiver for the transponder is in the ignition ring, that is the circle around the key slot.