Pinback button for the Black National Political Convention

The black button has green and red text which reads [BLACK / NATIONAL / POLITICAL / CONVENTION / MAR. 10, 11, 12, 1972 / GARY, IND.] The word "NATIONAL" is in red, and the rest of the words are green. The back is silver and has a wire pin. There is engraved text on the back which reads [MADE IN U.S.A. / (?) PEND.]. There is a symbol of a circle with an upward arrow going through it.