420A 420a belt - for alternator or alternator and water pump?

[idgtfts]

So I'm on rockauto looking for an alternator belt and multiple options come up. https://www.rockauto.com/en/moreinfo.php?pk=4206966&cc=1432931&pt=8900

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One says it's for Alternator, the other says it's for Alternator and water pump. How do I know which one to get? I'm not able to go under the hood and look at the belts to figure it out right now.

 

[99dsmer4g63]

-Non turbo cars have an accessory belt for just the alternator.
-Turbo cars the alternator and water pump run off the same accessory belt.
-non turbo the timing belt runs the water pump not the accessory belt

-Daniel

 

[idgtfts]

-Non turbo cars have an accessory belt for just the alternator.
-Turbo cars the alternator and water pump run off the same accessory belt.
-non turbo the timing belt runs the water pump not the accessory belt

-Daniel

thank you for the helpful response!