item_id isn't correct?

[rmvdev]

I've recently created a mini-extension that adds the movement date to the manage products grid and it works as it should however it highlighted an issue with the Stock Movements extension.

I've noticed with quite a few products the grid doesn't show any stock movements but inside the product you can see numerous stock movements, I added the item id to the stock movements grid and noticed the item_id shows as a 9 digit number that makes no sense?

I can't see the logic as to why its using a 9 digit item_id, I assumed the item_id was meant to be joined with the product entity_id?

Any help or guidance would be greatly appreciated