He's a big, mobile, puck moving, late-blooming RHD, whose arguably the best defenceman in the Finnish league right now and is undrafted.
I've seen him play a few times, and there's definitely promise. Remainds me a bit of Vatanen, except he's a lot bigger and more balanced as a player. Last year he played with Miro Heiskanen, and improved his defensive play a lot, this season he's found his offensive game in a big way.
One of the reasons he's gone under the radar is that he started as a forward but didn't have much success, and switched to D pretty late in his career. I could see him coming over to NHL next season, but I'm not entirely convinced that he can keep up with more competition, and would like to see him play a season in KHL or AHL to get more looks.