GenVibe - Community for Pontiac Vibe Enthusiasts

I'm a bit confused on the output speed sensor on my vibe. I replaced the one under and was going to get the one for under the starter. It looks different than mine. On the auto stores online one has a shaft with a slit in the shaft, The other looks like the one I just replaced but a little different. SO which one do I need? The one with the shaft is rather pricey so I don't want to make a mistake...I'll try to attach a pic of mine....