Planetary Gear Demonstrator, Size: 24cm x 14cm x 14cm, for explaining the principle of a planetary gear. By setting the internal sun and pinion gears into motion, Class Pack of 10
Spectrum Tubes Deuterium, glass tubes approximately 10-1/4in (260mm) long, central capillary portion approximately 3-1/2in to 4in (90-100mm) long with electrodes sealed at both ends and connected to lead wires protected by metal caps.