Amazon.com: Reebok Gymball - 55cm Exercise Ball with Dual Textured Non-Slip Surface for Maximum Grip - for Core Workout, Improving Stability, and Posture at Home or The Gym - Pump Included -
Reebok 65cm Exercise Ball | eBay
Reebok Fitness Gym Ball 65cm RAB-11016CY from Gaponez Sport Gear