What they say: Made from a lightweight thermo composite with sleek aero styling and design.
What we say: Not only are the thermo plastic arms spring-loaded, so they should hold most variations of bottle easily, but they are coated with a rubber-like gripper around the opening. This ensures a maximum bottle hold that actually benefits from a little wearing in.
Conclusion: A good effort that just tries a little too hard, at least when new. Improves with use over time.