Lens hood for 28-200?

[genericusername]

I have a 28-200mm f/3.5-5.6 for my xti and I was looking to buy the lens hood for it, which supplied by canon is the EW-78D. I would like to avoid paying the 40 bucks that canon charges for this 3 ounce petal-shaped piece of plastic and buy a generic one instead. I haven't been able to find a reasonably priced generic version but have come across the EW-78B II which is designed to fit the canon 28-135mm IS. Now the question: Does the 78 in the model name signify that this hood is 78mm in diameter, and if so will it fit my 28-200? The 78B does appear to be slightly longer than the 78D and I am wondering if that is the only difference.

[fubarhouse]

As far as I have observed, from my gear and others I've seen.
xxyy
x represents your diameter of the front element of the lens
y represents the design type - say crown, tube, long tube ect...
It may also appear as 78mm Type C ect...

No guarentee's, but this is as far as I know, hope it helps :)

[genericusername]

Yeah it does, thanks.