I ran across an old model Eotech (it's about 5 or 6 years old) the other day.  It's longer than the new AA battery types, has a thin steel hood, and loads N batteries from the front with an allen wrench.  The reticle is a small circle in a larger circle.  All of the controls are pressure buttons (elev., wind, etc.).  Anyone know the model number by chance?  The serial no. is 45XXX.  The new ones are around 102XXX.