What is the measurement of a bender ball?

I don’t want to actually BUY the bender ball because it takes way too long for shipping. I just want some sort of fitness ball the same size. But it doesn’t give the size in inches.
I’ve heard grapefruit and soccer ball. ???

Go here: Says 7 inches, and it’s written by Leslee Bender herself :

http://www.clubsolutionsmagazine.com/Pump_Up_Your_Pilates_Program.htm

Other balls (normally 9-inches) are available for way cheaper; but no video…Then again, there’s tons of websites which can show u the excercises, and it’s not Rocket Science! I wouldn’t order the Bender; INFAMOUS for Order issues (including a friend of mine).

How to Use a Stability Ball for Exercise

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