Uploaded April 2012 | Updated September 2026, 1 week ago

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What keeps these cups together? Suction or air pressure? These cups are very simple to use: no vacuum pump -- just two levers, yet they are incredibly difficult to pull apart. A great way to illustrate the concept that air pressure, not suction, is forcing the cups together. Available from Educational Innovations, Inc. at teachersource.com/product/pressure-pullers/air-pressure