I'm pretty sure this is something LMT makes in house or if not, who ever is making them is making them to LMT specs. If you find out differently please let me know because LMT single stage triggers are my favorite triggers. I have a couple but need a few more. I can tell you that they are not made by RRA or Armalite (or again if they are, they are are made to LMT specs) because I have gotten both RRA and Armalite single stage triggers before and both are different then the LMT's I have.
From a looks perspective, the only one I've seen that looks the same are the DPMS triggers but I've never had a DPMS trigger in my hands to compare side by side. Part of me doubts LMT is using DPMS triggers but weirder things have happened. Actually, I guess it would be cool if they are DPMS triggers because I know I can get DPMS triggers, and at a fair price.