Feature:-23 cm/ 9 inches. Easy to store and makes you able to do exercises anytime.-Equipped with a Foot Pump. You can inflate the mini stability ball quickly and easily in seconds.-Made of high quality environmentally PVC, non-toxic, safe and durable.-Anti-burst and Anti-slip matte surface can enhance friction.-Using the small workout ball can lengthen from head to toe. Improve overall stability and strengthen overall body muscle.Inflation Instructions:-Pull out the plug.-Connect the hose to the blue nozzle on the pump.-Choose a right size needle and attach it firmly to the blue conector.-Inflate the ball until it reaches to the mark.-Have the plug inserted at once.Care and Cleaning:-Keep sharp objects away from the small workout ball.-Store in a dry location away from direct sunlight.-If necessary, clean dirty spots with a combination of tea tree oil and water on a lightly moistened cloth.