The GRAV Rocker is an interesting pipe indeed. It's made in a way that is very interactive. You can spin it and rock it back and forth and it will stay quite stable. If you enjoy fiddling with your pipe its a great hand pipe. The body is a curved hollow structure so its a steamroller of sorts.
The silicone sleeve around this pipe makes it doubly durable from drops and tumbles. The mouthpiece also adds an ash-catcher to it to make your smoke sessions smoother.