My daughter is almost nine weeks old and just slowly discovers that she has fingers and hands. The Oball lets you grin from ear to ear over again because she realizes that the finger not only look exciting and interesting taste, but that they can also correct what. So the Oball is shaken vigorously through the area. The plastic is rounded and not sharp edges are feeling. He is a little elastic, so the little worm has no bump is when untrained swirled in his head through the area. The colors are great and you can perfectly hang on a mobile rod over the child and then they can practice cause and effect him. Super! Any time!