I replaced the Fuel Pump Relay #103. Pink one was on the car; replaced with red unit. Noticed that the unit that I took out has an extra 87b terminal. Anyone know the difference?

I've driven about 200 miles so far and the replacement relay has been great. No problems. So I'm just curious about 87b on the pink unit.

 

I wish I could tell you.
One must be from an older car where they used if for something.