Invisible Pink Unicorn lapel pin. A pin on the rear can be pushed through a button hole or through fabric and then is held in place by a separate clasp.
Because the Invisible Pink Unicorn (IPU) is invisible, no one can prove that she does not exist or that she is not pink.
The IPU is used to satirize theistic beliefs, taking the form of a unicorn that is paradoxically both invisible and pink.
It is a rhetorical illustration used by atheists and other religious skeptics as a contemporary version of Russell's teapot.
Measures 1" diameter (2.5 cm).