Thank you, Flapjack! Yeah, this is a very old model -- from 1989, made by Citadel. Some people call it "Mark 1" Terminator armor, many call it "Saturnine Pattern" Terminator armor, but officially it has no name yet and has barely every been mentioned or acknowledged. I bought two way back then, and so I still have one that's unpainted. Here's a link to its info:
https://www.miniatures-workshop.com/lostminiswiki/index.php?title=Image:Citadel-410609-01.jpg
What's cool is, this painted one has pegs in its feet so I can take it off the display base and put it on a regular flat base for play. Fun!