I thought that the red spot keys were the ones that went with the factory alarm systems. The keys themselves didn't have any electronics like the new transpoder keys, but it just denoted that the car had a factory alarm system. When you lock the car with the red dot key, it arms the alarm system and if a different key is used to unlock, such as a valet key or other spare, the alarm will be set off since they lack the extra notch to trip the microswitch in the door tumbler.