These heavy duty Magdeburg hemispheres are closer to the original version than plastic or rubber models. Thick cast iron walls and large steel handles make this item extremely durable. Plated brass valve and precision machining prevent leakage. Additional Info: these heavy duty magdeburg hemispheres are closer to the original version than plastic or rubber models. Thick cast iron walls and large steel handles make this item extremely durable. Plated brass valve and precision machining prevent leakage. Package Size(L x W x H): 7.25 X 4.5 X 4.25 (IN) Categories: Matter, Vacuum HTS Code: 9023.00.0000 UNSPSC: 6.01046e+007 Country Of Origin: CHINA