The red one came in defective, other three work as they sbould be. The top number of red one is malfunction so any number can be used to open the lock. For example, if we set 1-2-3, it will work if we try to open with 2-2-3, 3-2-3, 4-2-3, etc. The lock will open. It was such a hassle trying to contact seller so I will just keep it.