It's a Garmin Oregon 450.

I'm not exactly sure where I lost it, but it either fell out of my pack, or I left it on the ground at a rest stop. It's a long shot to get it returned, but my name and phone number is in the startup screen so if someone finds it, they can choose to contact me if they want to do their good deed for the day.

I'm posting here on the off chance that someone here reads about it, and then finds out about someone finding a GPS elsewhere. Maybe a little peer pressure will convince the finder to contact me.