I was browsing the web around to find a key for window 10 pro. A lot of people where remanding to buy from www.kinguin.net/ but the price have go up a bit. Think it near 40$, now! So, I made more research and find scdkey.
You can buy it via this affiliate linkwww.scdkey.com/sk/window10pro
I use this key for one month and did not have any problems with and the service of the site has been reliable
OEM = Original equipment manufacturer.
This mean you will not have aced as much support from Windows, you are your one manufacturer. Personally, I never use support form windows and always find my answers by myself on the web. OEM KEY are perfect for person like me. Hope it helps some of you that did not know about the site.