The ball has two seats inside, and outside there are two spots for one or two avatars to volley the ball (and anyone inside) back and forth
Thanks to Lindyxx and Anotherneko for helping demonstrate. Here's Anotherneko going for a spin:
Me and Neko playing with Lindy!! (big file)
Note to developers: this product has a repeating texture, the texture repeats ten times around the ball. If you want a similar base with a non-repeating texture map try Super Bouncy Fun Ball