It's a novelty item, the point is it makes it easy to find in the dark: http://unitednuclear.com/index.php?main_page=product_info&cPath=2_8&products_id=480&zen

It's a novelty item, the point is it makes it easy to find in the dark: http://unitednuclear.com/index.php?main_page=product_info&cPath=2_8&products_id=480&zenid=7ddf26f4c1762f9b460df47a5721a853 http://unitednuclear.com/index.php?main_page=product_info&#3... Seems benign to me, since beta radiation won't penetrate the glass. See also http://en.wikipedia.org/wiki/Tritium_illumination http://en.wikipedia.org/wiki/Tritium_illumination