Crush-Proof do not meant non-destructible. Ball Pit Balls are for use by Kids of the appropriate age/weight. They were air-filled, will give when pressure on, and will return back to shape when pressure released. Ball Pit Balls are not Puncture-Proof, and not designed/intended for pets or animal use.
With Ball Pit Balls, the Size Does Matters. The larger Size the Balls are, the longer lasting & more durable the balls will be. Jumbo 3" Balls are about 2.3 times the fill volume when compared to the 2.3" Balls ( most popular size sold on Amazon, Walmart and other Big-Box Stores ).
With Ball Pit Balls, the Weight of the ball Dose Matters. The heavier the Balls are, the longer lasting & more durable the balls will be. Most Popular Weight: Commercial Grade 3" Balls: 12~15 grams, Jumbo 3" Balls : 6~9 grams, Large 2.5" Balls: 4~6 grams, Medium 2.3" Balls: 3~5 grams. The My Balls Brand Ball Pit Balls are always built with the most materials for longer lasting durability.
To calculate the amount of balls needed, your would need to know the volume of the area you intended to fill in Cubic Feet ( 7.5 Gallons = 1 cubic foot ).
Balls DO Leaks during use. Like an unopened can of soda even sitting on the shelf, will lose the bubblies after 6 months after production. We can't stop this natural process but we can sure slow it down by increasing the amount of material used to build the balls. The heavy the ball is, the more durable the balls will be.
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