This is for two key chains to share between a couple. One of you carries the key and the other carries the lock to remind each other of your relationship. The key is not made to fit into the lock. The charms are made to match in style and size and are symbolic of the saying on the card. They both come together on one card that says "Youve got the key to my heart!" The heart lock is about 1 1/2 inches long and a little over an inch wide, and the key is a little over 1 3/4 inches long and 3/4 of an inch wide.