In conclusion, it can be stated that a plastic scintillator with a light output proportional to the energy of the outer electrons does exist and can be used to advantage for the spectrometry of outer electrons within a wide energy interval, in principle, from zero electron energy on. At low electron energies (0–20 keV) this plastic scintillator has a light output which is considerably larger than the light output of other plastic scintillator at the same energies; therefore this scintillator is useful for the detection of low-energy electrons.