Road to VR on Twitter: "[From the Archives] 6DOF before 6DOF was cool. Oculus Rift DK1 development kit with Razer Hydra 6DOF controllers; some very early projects allowed users to attach one
Collections – Hydra PC
How to Use Razer Hydra Motion Controllers in SteamVR | Tom's Guide Forum
Hydra evolved: Sixense Stem launches on Kickstarter, we go hands-on with a prototype (video) | Engadget
KOTION EACH G2000/G9000 Gaming Headset – Hydra PC
Razer Hydra Review
Sixense Wireless Motion Tracking Development Kit Announced, Effectively the Hydra 2 – Road to VR
Razer Hydra Sale: 50% off for Oculus Rift Through April 25th