http://www.postureball.com/
http://www.fitterfirst.com/
Personally, I would go with the DuraBall Pro (from the fitterfirst.com website). All of the PostureBalls I had popped and I fell on my bottom, rather harshly. When the DuraBall Pro ruptured, it slowly deflated and allowed me enough time to get off.
http://www.fitterfirst.com/
Personally, I would go with the DuraBall Pro (from the fitterfirst.com website). All of the PostureBalls I had popped and I fell on my bottom, rather harshly. When the DuraBall Pro ruptured, it slowly deflated and allowed me enough time to get off.