Exergia-Candle-Powered-Stirling-Engine-Kit-Exergia-190638-This-easy-to-assemble-kit-will-demonstrate-the-direct-conversion-of-heat-into-kinetic-energy-Based-on-a-Beta-type-Stirling-engine-that-operates-by-the-cyclic-compression-&-expansion-of-air-powered-by-the-heat-from-an-ordinary-tea-light-All-the-parts-required-for-construction-are-supplied-&-only-simple-tools-are-required-Exergia-190638-Science-Kit-Set-14-Years-&-Over