JAO suggested several less expensive alternatives to Tumbl Trak including the AeroMat® Peanut Exercise Ball $42.99 on BallsnBands.com:
Even cheaper is the Danskin Now Ultimate AB Ball $19.00 at Walmart:
I love inflatable equipment. But, in the real world, in most gyms, … I’m estimating a 3yr lifespan.
Some punctures won’t be repaired.
Gymnastics Coaching.com 