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This product is mainly used in junior high school physics to prove the existence of atmospheric pressure and demonstrate the famous Magdeburg hemisphere experiment.

Two rubber hemispheres with pull-rings align with each other to form a closed container, and then press lightly. The pressure difference between the closed sphere and the outside atmospheric pressure will suck the two hemispherical balls tightly, so that they cannot be used in a certain tension ring. The two hemispheres are separated.

Size: chassis diameter 117mm/4.6 in

Material: rubber chassis + metal pull ring

Weight: a pair of net weight is about 350g