Google just announced that 4K movies are now available from the company’s Google Play Movies store in the United States and Canada, with a selection of over 125 titles to start. 4K content has been gradually trickling out across Play Movies over the last few weeks, but today Google is making the UHD kickoff official.

Google says all movies on the Play store use the VP9 codec, which is designed to produce an ideal mix of sharp picture quality and reliable streaming. You can purchase 4K content from an Android device or Play Movies on the web, but it can only be viewed on select products right now: the Chromecast Ultra, Sony Bravia Android TVs, and Xiaomi’s Mi Box 3.

For a limited time, Google is giving away one free 4K movie to buyers of the Chromecast Ultra, though you’re limited to a list that includes Ghostbusters and Captain Philips. That’s still not a bad deal, seeing as plenty of digital 4K movie purchases still go for $19.99 and often more. Bringing 4K to Play Movies certainly boosts the amount of UHD content that’s available to Chromecast Ultra owners, but whether it makes up for the absence of Amazon Video will depend on what you like to watch.