EXTENDED BALL LIFE: Increase new tennis ball lifespan 10x or more with the Ball Rescuer. This kit includes one Ball Rescuer, 2 extra O-rings, 5 g of silicone grease for optimal lubrication, perfect operation, and leak prevention, a pump with a pressure gauge, and a compatible tennis ball container with a set of 3 balls inside.,COMPATIBLE CONTAINERS: The Ball Rescuer is compatible with containers that do not open the expansion slot of the clamp more that 2 mm (see picture).
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