From the mode description:
The Stirling engine's flywheels are connected by a rubber band to four flywheels on the Ferris wheel, powering its rotation. Made in Germany, the kit's parts are made from machine tooled solid brass, stainless steel, and aluminum components on a walnut stained wood base. Ferris wheel: 9" H x 5" W x 4" D. Stirling engine: 5" H x 6" L x 4 1/4"
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