Sony announced today that its PlayStation VR headset has reached the 3 million sold milestone. It has also sold 21 million PSVR games.

PSVR launched in October 2016 as an accessory for the PlayStation 4. While other VR headsets, like the HTC Vive and Oculus Rift, require powerful (and expensive) computers, the PSVR works with the relatively cheaper PlayStation 4. This has helped PSVR perform better than the competition.

The Elder Scrolls V: Skyrim VR has been the platform’s most popular title, according to Variety. The original version of Skyrim launched in 2011, but Bethesda has kept the game relevant and profitable by porting it to new devices.

The PlayStation 4 has sold 82 million consoles, so only a small percentage of console owners have purchased the PSVR. The headset comes in bundles that include a PlayStation Camera and a game (like Doom VR), and these start at $300. Although it’s a cheaper option than the competition, PSVR is still an expensive endeavor.

But Sony’s VR investment is putting it far ahead of its console rivals. Microsoft’s Xbox One and Nintendo’s Switch don’t have VR support.