Seems impossible: Inflate an 8 foot long bag using only 1 breath of air! It’s a brand new science demonstration that illustrates the many properties of air. Each WINDBAG is 8’ long, 10” in diameter, and hold 44 liters of air. How can such a bag be inflated using only 1 breath of air? The secret is scientific, of course. The illustrated instructions include over a dozen fun and educational activities. Package includes 4 Windbags.