Off-ice training puck matched to the weight of a standard regulation puck at 6oz. Practice stick handling and shooting anywhere. The dispersing inner-core weight keeps the puck from bouncing or rolling away and simulates ice resistance. Made from a non-marring flexible material that creates a softer impact and will not damage floors. Works best on smooth off-ice surfaces like garages, gym floors or sports courts. U.S. Patent Pending #7067933 How it started: Ninja puck was created for playing off-ice hockey with my son after we were unable to find a good option on the market. We tried balls that rolled too fast, ice pucks that were heavy and left marks, and tape balls which were inconsistent. Ninja puck is weighted and slides just right on smooth surfaces, which simulates the way a puck slides on ice. It also doubles as a fun fidget toy and we are pretty stoked about the cute ninja design.