This is a cat toy: a hollow sphere with several small bells inside, and the wall of the ball is cleverly carved with lifelike cat patterns.

My daughter's cat really likes this toy—of course, like most cats, it's always ready to chase and play with almost any round little ball. The cat pattern is from MaakMijnldee's cookie mold series, numbered 35495; the other patterns are directly embedded in the openSCAD code.

At the top of the sphere, there is a pentagonal opening. The lid is printed separately. After the bells are put into the sphere, they are fixed in place with acetone or glue. These bells are purchased from craft stores and are often called "jingle bells". I chose the half-inch size products.