On my 97 sti, the Air con belt has been taken off. I'm fairly sure its the same belt that does the alternator as well, but it looks as though a smaller one must of been put on?

Mines looking a little worn and I want to get a replacement shortly, any ideas anyone?

 

Hi, the power steering/ alternator belt has one more groove in it than the air con belt, which is narrower.
Look at your crank pulley, you'll see what i mean.

Mit