If you know you want a PlayStation VR, you better get up early.

Sony announced today that the last chance for PlayStation 4 owners to preorder the PlayStation VR headset will start on June 30 at 7:00 a.m. Pacific on GameStop’s online store. If you want to guarantee one when it launches on October 13, you better be ready. Analysts at research firm SuperData predict that the VR market could generate $40 billion in revenues by 2020.

“Supplies are limited, and this is your final chance to preorder. If you miss out, we will have product available in retail stores nationwide at launch,” Sony notes on its blog.

The PSVR comes in two bundles. For $500, the launch bundle includes a PlayStation Camera, two Move controllers, and the game PlayStation VR Worlds. The $400 core bundle just comes with the headset, stereo headphones, and VR demo disk — but players will need to acquire their own PS camera, which PSVR requires to work.

Virtual reality headsets for the PC like the Oculus Rift and HTC Vive launched earlier this year at $600 and $800, respectively. The PSVR is the first one in this new age of VR built for a console. Its lower price compared to its more expensive PC counterparts could attract a larger audience.