Nice size for handling comfortable in adults' hand. The colorful buttons are easy to push. The material used to make the ball is very durable and will last. There's one empty circle and you push the colored balls around utilizing the empty space to match the color of the ball with the ring outside the circle. There's a sponge center in the ball that allows the colored balls to slide from one space to the next when you press on them. Mix it up the same way you solve it. Your logo is welcome. Size: 2.76" x 2.76" x 2.76".
