I think that's a Chinese knockoff of an MS 290 or MS 360ish saw. If I'm correct the Stihl bar is worth more than the saw. If it's a Stihl, somebody put a bunch of Chinese plastic on it.
Lot of after market parts. Recoil Oil and fuel caps Plastics What ever else you can’t see I’d say 039 hybrid after market due to screw on caps.
Looks like a Chihl Model # POS If oem, they're not a bad saw at all. Lots of torque. That one looks to have some AM parts on it But the bar is a dandy
I want to clarify what I posted above. The 029-039 style of saw is a very capable saw if it's all oem. My pos comment was only due to the apparent Chinese parts. When these parts are on the outside, we expect that the inside could be the same. CL sellers will advertise an ms390 as an ms460 with a 28" bar on it in hopes that an unsuspecting buyer won't know the difference. It's best to approach such saws with good knowledge of what you're looking for.