Advantages of Tumaz Wobble CushionOur cushion is made of thicker and more durable material compared with competitors. Easy to inflate or deflate with the complimentary hand pump Perfect gift for who lives a sedentary lifestyle Sitting on the cushion automatically activates your core muscle which helps you maintain correct sitting pose and alleviate neck or back pain. Wiggle seat for children: children love the cushion. It helps them remain seated and focus on the class. SpecificationsDiameter: 13 inch Weight: 2.2 pounds Material: Phthalates-free PVC. Meet US California Proposition 65 standards.About TumazWe are a bunch of friends who are enthusiastic to fitness for a long time. Some love yoga while some love weightlifting. Some love running while some love sports. Although our interests are different but our goal is the same - keep fit and get healthy.With our enthusiasm and exercise experiences for years, we are proud of presenting our fitness products to you. Our products not only use premium material but also have lovely designs. Moreover, the price is attractive given its premium quality.Our vision is to be the most customer centric fitness company. So, we care what you care - function, safety, looks, and price!60 Days Worry-Free Guarantee We care what you care. Our goal is to make you 100% satisfied with your purchase. With the confidence of our products, our money back warranty is 60 days which is two times longer than Amazon's standard return policy. So, if you are not 100% satisfied with our product, simply return it within 60 days and have your money refunded. No reason given. No weasel words. No hassle.