I'm guessing it's a first generation. It says EOTech on the bottom as well as built July 1999. There is no adjustment for elevation that I can tell, possible adjustment for windage via sliding the reticle. It takes 2 N batteries and access to them requires an allen wrench. There are no other markings besides that and the serial number which is 787XX. Anyone know the model number and possibly an online source for a manual?
Thanks.
http://i367.photobucket.com/albums/oo112/coltar15/Photo_11-2.jpg
http://i367.photobucket.com/albums/oo112/coltar15/Photo_11-1.jpg

I found some instructions last week for an Eotech. It was talking about how it had only windage adjustment. Elevation adjustment was with the mounting system. It turned out it was instructions for a sight made for a bow, not a gun.

if I remember right this one had reticles you could get for it,

call EO and see if they'll swap for a 557

Do you think they'll trade me straight up?
I picked it for cheap cheap cheap, less than clone prices. I'm just trying to get a model number or something to help do some research.

That's the original Holosight - actually sold by Bushnell under license from Eotech before any were sold under the Eotech name.  It was released in 1996, and you could get replaceable reticles for it.  If this one lets you replace the reticle, it's a model 400; if not, it's a model 500, according to the info I've seen.

Here's a review of them from back in the day:
http://www.snipercountry.com/InReviews/Bushnell_Holosight.asp

and another one that shows some of the reticle options:
http://www.notpurfect.com/main/holosight.html

Yeah I'd found those already. If you look at the pics of mine its a solid one piece unit, not the two piece look like the ones in the old article. Mine also doesn't have any windage or elevation adjustment knobs. It is also not marked Bushnell anywhere on it. I'm not sure if windage can be adjusted by loosening and sliding the reticle to one side a bit like you do with pistol iron sights. I guess I'm somehow hoping this is a special dedicated model for the M4 or something. It'll still work for what I need it for though. Thanks for everyones help so far, it looks like a 400 but is far different at the same time. Does anyone have a user manual for the 400 or link as I think operation will be the same besides windage and elevation?

Doh!  You're right, I didn't look closely enough.

When I looked in my archives, I found I have some pics of a 1999 vintage Eotech - I'm guessing this was the first model marketed by Eotech.  It looks like yours is missing the protective hood, and I don't think they came with the archery sights.

This one has windage and elevation adjustments on the back and side, as you can see in the pics below, and yours definitely doesn't have that extension at the back with the adjustments.  I'm thinking it is an archery version, and is adjusted with the mount, rather than the screws - the Eotech 520 archery sight has a micro windage adjustment, but recommends a mount with elevation and coarse windage adjustments.

ETA - I found this page from the internet wayback machine:
http://web.archive.org/web/20010607005025/www.eotech-inc.com/archery/mainframe.html

It shows the Model 420 archery sight has no windage adjustment, while the 520 (the current form factor) has windage only and is shorter than the 420.  I'm starting to think yours is a late model 1st gen, right before they changed to the 2nd gen that looks like the current ones.

Unfortunately, I don't remember where I got these from - probably here or another gun board.  The label is washed out in the pic, and I can only get Manufactured March - Serial 699xx out of it.

If you do find some info on it, be sure to post it back here.

You da man!!!
Well I guess I'll dig the bow out and try it out on it. No returns on the 69.99 EOTech from Cabelas bargain cave. It all makes sense now with the lack of adjustment.

I may not have a lot of posts here, but that's only because I utilize the search function when I have questions and usually my question has been answered many, many, many times in the archives of this great site.