DriVR Quest Pro Adapter

Not only works, but with a silicon cover on, as well (minor modifications to the side of the cover handle sections to fit in the DeadEyeVR 3D cup itself.) Really secure for the Pro Touch controllers, which because of the lack of a ring have nothing much to hold them into an extension handle, other than the ones that attempt to clamp down on the wrist strap, or made a 3d printed side clamp (which didn't hold well under full drives even with the handle strapped in with hook & loop.) DeadEyeVR's Touch Pro adapter simply works better since it holds from the top of the controller - the side straps do not interfere with the on-board tracking cameras.