Trijicon RMR type 2 auto adjusting model. I have had this for 4-5 years and it has maybe seen 200ish rounds. I bought it to go on a range gun and it had spent more time in the safe than on a range gun. Only selling to help fund a RMR HD for another gun. Will come in Trijicon hard case with the screws that is currently holding the optic to the slide.