All Stereohype button badges available at stereohype.com are classic high quality one inch (25mm) metal back badges with so-called D-pin (although it looks more like an 'e'). Tiny stickers at the back mention the artist, release date, series number, etc. The growing collection of these mobile mini canvases – featuring over 1,200 individual designs by over 350 international graphic designers, illustrators, photographers and artists – consists of all B.I.O. (By Invitation Only) contributions, winners of Stereohype's annual button badge design competition and additional series such as the special collaborations: AFOMFS Series, MICA Series, 10x10 Series and Emoji Series. Badges are manufactured in the United Kingdom.