I've had it so long I don't remember what it is - I think it is an Armalite 2 stage from an AR10 but not sure.Doesn't look like current Armalite offerings.

Took this to the gunsmith here and he only had to glance at it and said it was an old LMT trigger. They don't have parts any longer for it though.
TR
He's right - knowing where to look I found this:
Almost looks like I stole their picture...
Love this place!!!

The difference is that the hammer spring in your picture is installed correctly.
Heh - didn't notice that. Funny cause that's off their web site!

The ArmaLite two stage has a dico as wide as the hammer hook. Never wear out.

If you have enough money to shoot out your disconnect,

you can afford a new trigger every 10,000 rounds...