Looks like a NEMA 6-15 or 6-30, which is a 15A 250V AC socket, or 30A 250V AC socket respectively. Your image, however, if you look closely shows the socket labeled as 20A 250V...
In either case, the plug is a NEMA 6-15 or 6-30. If you get the NEMA 6-20 plug which is rated 20A 250V one of the blades will be rotated 90 degrees and won't fit the socket.
Clear as mud, right? Search the NEMA straight blade reference chart and you'll see what I mean.
HTH
Thank you very much for the answer, but that only leads to more questions, lol.
So, would it be safe to assume I would burn down my house if I treated it as a 30A 250V socket? By just treating it like a 15A 250V, I should be good correct, since it is under the 20A limit?
So if I can use it as a 15A 250V, I could theoretically get 15 * 250 = 3750 watts out of it?