Valve has announced that it’s shipping a new version of its experimental SteamVR “Knuckles” controllers to developers, and it’s posted a lot of detail about the controllers online, including video of a Portal-themed playground for testing them. The Knuckles EV2 substantially updates Valve’s earlier design, and although it’s not a consumer product, it’s looking more polished — and even less like the earlier Vive controller.

The Knuckles controllers, originally shown off in 2016, give users a fuller hand motion range than most VR controllers. Instead of holding them, you strap them around your hand, so you can open and close your fingers normally without dropping the controller. Capacitive sensors detect when individual fingers are touching the controller, so you can do things like pick up objects by naturally closing your fist, instead of hitting a trigger or grip button.

The EV2 controllers add some new elements to the original design. There’s a new force sensor that detects actual grip force, and instead of a big Vive-style trackpad with a couple of buttons on the side, each Knuckles EV2 controller has a pair of face buttons, an analog stick, and a much smaller elongated “Track Button” in the center. (It’s actually a thumb-shaped trackpad with a force sensor underneath, not a mechanical button.) Developer Colin North tweeted a picture of the new controllers compared to the old ones; the EV2 is on the left side.

Valve created a demo called Moondust (unrelated to the Jaron Lanier game of the same name) to showcase the abilities of these new controllers. It’s only available to developers with the kits, but you can watch four minutes of gameplay below, and there’s a lot of detail about the demo on Valve’s forums. Among other things, you can crush rocks by squeezing your hands, drive a buggy with the new thumbstick, and build a space station by precisely picking up its pieces and fitting them together. Like earlier Vive demos, the whole thing is set in the world of Portal, where Aperture Science is sending robots to process rocks on the Moon.

HTC and Valve partnered to launch the Vive headset in 2016, but we haven’t seen a lot of new collaboration since then, as HTC has developed its own tracking puck and launched a high-resolution headset, and Valve has flirted with other hardware manufacturers. So while it’s possible these will come to a new generation of Vive, there’s not a clear path from this development kit to a mass-market product. That said, these controllers look pretty good — so we wouldn’t be surprised to see Valve showing them off more widely soon.