Stanton radioactive static eliminator, thought to be thallium 204. Tl-204 has a half life of 3.78 years so in 2008 there will only be 0.02% of the Tl-204 remaining. Tl-204 decays to the stable isotopes of mercury Hg-204 and Hg-200. Stanton radioactive static eliminator 1960