Timberbrother Anti-Burst Exercise Swiss Ball 55cm Diameter with Pump for Yoga, Pilates, Fitness, Physical Therapy, Gym and Home Exercise (Violet) About this item Due to the flexible PVC material, some may require time to get fully stretched. Please inflating 80% of size on the initial inflation and left the ball overnight to stretch. It will reach its final size after 1-2 re-inflation
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