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.
Meldes Vibrating String Apparatus, consists of a string and an oscillator to generate different frequencies, Requires 6 V, 50 Hz power source, with 4mm plug leads, Weight (lb): 1.4, Length (in):11.0, Width (in):6.0, Height (in):3.0