Beach ball
A beach ball is an inflatable ball for beach and water games. Their large size and light weight take little effort to propel; they travel very slowly and generally must be caught with two hands.
The beach ball's invention is usually credited to Jonathon DeLonge in California in 1938.
Beach balls range from hand-sized to over 3 feet (1 m) across or bigger. They generally have a set of soft plastic panels, with two circular end panels, one with an oral inflation valve, intended to be inflated by mouth or pump. A common design is vertical solid colored stripes alternating with white stripes. Some are printed with advertisements or company slogans, or as globes.
Some manufacturers' claimed "diameter" of a beach ball is actually the tip-to-tip length of a deflated ball (approximately half a circumference), or even the length of the panels before they have their ends cut and joined into a beach ball. Thus the actual diameter may be about (≈ 0.6366…) of the nominal "⌀".
Beach ball sports include water polo and volleyball. While they are much less expensive than the balls used in professional sports, they are also much less durable as they are made of soft plastic. Giant beach balls may be hit around between crowd members at concerts, festivals, and sporting events. Many graduates use beach balls as a prank during ceremonies, hitting them around the crowd. Their light weight and stability made them ideal for trained seals balancing a beach ball on their noses. They are a popular prop in swimsuit photography. They are bounced around crowds at cricket and baseball games but frequently confiscated and popped by security.
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