This is a novelty item and not for continous or heavy training. It's made out of hard plastic making the ring flimsy. the ring now serves as a place to put keys but not for heavy weighted keys. i created this as my fidget spinner for my keys , but there are martial applications as one can become creative with this novelty. But once again this is not built for heavy and hard use. Check out my videos for modificaitons to be able to play and train with it.