Question: Can you revive old tennis balls?
Answer: Balls lose bounce when the air inside them seeps out through the rubber, reducing the internal pressure. Old tennis balls can be repressurized to regain their bounce and will perform well as long as they still have most of their fuzz. A repressurizer is a closed chamber into which you pump air so that its pressure forces air back into the balls. Repressurizers come in capacities from three to several dozen balls.
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