This looks familiar somehow, but I can't place it. Have you posted it elsewhere on the internet?
My gut instinct is to say no, I'm afraid. From what I've seen, the shape is too curved for one thing, hooks had sharp points. Obviously it could have been worn down, but one can try to extrapolate the original shape from its pre-eroded state. I think the biggest stumbling block is the size, belemnite hooks were very small, maybe only a few millimetres long and this looks much larger. Don't forget that belemnites had two rows of these things on each arm and ten arms in total, scaling that up from the size of your fossil implies the belemnite would have been massive.
I assume you found this in the US? The largest belemnite was Megateuthis which is, as far as I know, unknown from the US and is mainly found in Europe and Indonesia. Also, hooks are very rarely preserved which makes the chances of you finding one very remote indeed I'm afraid.
Apologies for an unwelcome answer. Now we have to work out what it actually is of course!
Yes, it was found in Arkansas, south western part of the state. I did post it on the fossil forum right after I found it. I'm a bit disappointed but I may live. Anything you can tell me would be appreciated and thanks!
I am quite sure it is a small Rudist bivalve. This from someone who spent the weekend picking up Pinyon pine nut shells and Juniper berries thinking they were small goniatites (I have learned to avoid the deer droppings).
Don't worry about it Roz, I'm sure we've all done it at some point. Three years ago or so I posted images of a tooth I found on a beach to a couple of fossil forums to identify as I thought it was a Cretaceous marine reptile, but it turned out it was a fox. What an idiot.