The U.S. Postal Service on Monday unveiled the image for its upcoming stamp dedicated to the memory of slain politician and gay rights activist Harvey Milk.

The stamp is based a circa 1977 black and white photograph of Milk taken by Daniel Nicoletta.

Milk was the first openly gay elected official of a major U.S. City. He was elected to the San Francisco Board of Supervisors in 1977 on a pledge to back gay and lesbian rights. The following year, Milk was killed by Dan White, a former supervisor.

According to the Gay and Lesbian Victory Fund, a group that supports openly LGBT elected officials, Milk is the first openly LGBT elected official to be featured on a U.S. postage stamp.

A dedication ceremony will be held on May 22 at the White House.

Visit to pre-order the stamp.

(Related: San Francisco considers renaming airport after Harvey Milk.)