Earlier this year, Valve introduced the world to its vision of bringing PC gaming to the living room with SteamOS and Steam Machines. While hardware makers won’t have Steam Machines on the market until next year, Valve said it would be sending out 300 prototype machines to beta testers at some point in December. Turns out that “some point in December” is this Friday.

Valve announced today that its 300 prototype Steam Machines and Steam controllers will be shipping out to 300 beta participants on December 13. It will also be sending out notifications to said beta participants today at 5 p.m. EST/2 p.m. PST. Those who are selected will get a special badge on their Steam Community profile and will receive a number of free games that run natively on SteamOS.

That’s all good news, but like always, there’s a bit of bad news as well. Valve’s original plan was to open the beta to PC gamers around the world, but the company confirmed today that the beta had to be restricted to US citizens only. Why? You can blame international regulations for that.

We’ve had to make the difficult decision to limit our beta to the U.S. only, because of regulatory hurdles. This was not our original plan, and it means we can’t collect beta feedback from Steam customers world-wide, which is pretty unfortunate. All things considered, we’re sure it was the right decision, because the alternative was to delay the whole beta beyond the point when we’d be able to incorporate any feedback into the 2014 products. This decision only affects Valve’s 300 prototype units; the commercial versions of Steam Machines that are for sale in 2014 won’t be affected by this. More information on those will be announced at CES on January 6.

As a consolation prize of sorts, Valve says that SteamOS will be available to download on Friday. This version of SteamOS will be available to both individuals and OEMs, but Valve recommends that anybody who isn’t familiar with Linux should wait until later next year to download it.

As an added bonus, here’s a picture of the production line where the Steam Machine prototypes are being built:

If you get into the Steam Machine beta, be sure to let all your friends know. You’ll be the the object of their jealousy for at least a few months until Steam Machines become widely available.