Tumbl Trak Air Barrel, Vinyl The Air Barrel is a very simple, yet extremely versatile, multi-purpose training device While it may look like a foam octagon or barrel, it is filled with air and therefore is BOUNCY Because it is bouncy, it can be used for many drills that cannot be done with the traditional foam shapes The Air Barrel can be used for tumbling, vaulting, bar and vault skills and also has many applications for teaching body awareness and control