... but cheaper.2), generally, how long can people stay in the water ball?a). 15-20 minutes rides ... every 30 minutes3), HOW DO YOU GET INSIDE OF THOSE BALLS?We have a zipper!4), HOW DO I BLOW THEM UP ... ?Use an air blower.5), GREAT FOR KIDS THE "BIMBOBALL"Water balls/rolling ball are a ... on the water, that is .....with a little practice.A really great way to practice to have ...