The boards in the GRADED version have milling on the convex side of the board minimising the risk of pinching of fingers. We noted that the parents who see a curved balance board for the first time are accompanied by concerns about pinching of fingers. Our sons experienced themselves painful crushing of little fingers. This inspired us to design an original solution - a cut on a convex side of the board thus GAKKER in the Graded version retains all features and benefits of the classic balance board and minimises the likelihood of painful pinching of fingers at the same time. The Gakker Graded board model is registered in the European Union Intellectual Property Office under the following numbers 006032009-0001, 006612370-0001 and 006612370-0002.