A simple wooden model, to simulate the solar system focusing on the Earth and the Moon, around the Sun. The moon also revolves around the earth, and both together around the sun. Powered by 2 standard finger batteries (not included in the kit) Estimated build time: 10 minutes. The styrofoam balls come in white, and can be painted independently. The parts arrive connected by wooden plates, and must be separated and assembled according to the instructions. The instructions are clear, with a picture for each step, and text in Hebrew where required. The kit does not contain batteries!