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.