Osclass Site Visitor / Traffic Stats / "POST / HTTP/1.1" 200 417 "Osclass 390" "-"

2605:6400:3:fed5:1000:101:0:2 - - [10/May/2020:04:35:13 +0200] “POST / HTTP/1.1” 200 417 “Osclass 390” “-”

I see into visitor stats a lot of above given line… What does it means?