Question about Tokina EL 28mm F 2.8 lens

I'm relatively inexperienced when it comes to SLRs and lenses, but I've got a pretty basic understanding. I've been shooting on an Olympus OM-PC (OM-40) with the stock lens, a Zuiko MC Auto-S f 1.8. I figured I'd go see if I could find a decent wide angle lens and I kind of settled on the Tokina that I found on ebay. The description said that it was made for the OM system, but it came in today and it does not fit on my camera. The stock looks completely different than my Zuiko. I looked up the Tokina lens and I think there's a few different versions of the same lens. I 've seen a listing for the same lens, but for Pentax's and Minolta's (MD I believe it is). So my questions are 1) if it is true that this Tokina lens is available for other cameras and 2) if I was given the wrong one.
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is this a good buy?

Contact the seller, make sure that it's for the Olympus Mount (Manual Focus) if he's not sure, or it's not the right mount, it's not a good buy.

If it is correct, then yet, go for it.

very nice info

Very good information

I am also Agree that it is really a very awesome and Interesting Information about Tokina EL 28mm F 2.8 Lens.

Here is a Tokina original lens 28mm. numbered 052 and 8406625 it is also F 1:2.8 and will fit multiple cameras. Additional adapters may need to be purchased separately to use with your camera.
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