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.
Atmospheric Mat with Hook, Measures 10.5 x 10.5 In, durable, thick rubber mat has a simple design that demonstrates a powerful concept - Atmospheric Pressure
Spectrum Discharge Tube, Mercury Gas to show spectral lines of pure substances. Tubes approximately 260mm long, central capillary portion approximately 3-1/2 to 4 (90-100mm) long with electrodes sealed at both ends and connected to lead wires protected by metal caps