English: A small button from an ionization-type smoke detector containing 1 microcurie (141 nanograms) of americium-241 dioxide (241AmO2) inside. The metal casing is aluminum.
This image, originally posted to Flickr, was reviewed on 18:21, 9 January 2016 (UTC) by the administrator or reviewerww2censor, who confirmed that it was available on Flickr under the stated license on that date.