It"s IDENTICAL to any top brand balance / stability discs out there by design, weight, & material. Don"t be fooled by a competitor review but believe in what you see & our store"s feedback * Size: 13"; Color: Blue. Shipping weight: 3 lbs * Textured surface as shown to massage foot surface and improve grip * Pre-inflated to a level suitable for most uses (NO air pump included. Search "isopump" for compatible pumps) * Use for standing, kneeling and sitting & push up to develop balance & stabilization