Grey envelope with typewritten address to Rolph A. Baum, with return address above to Peter Israel Hirschfeld. Includes brown censor tape on back. Information Provided by Michael D. Bulmash: A law enacted August 17, 1938 required Jews with non-Jewish forenames to assume the name Sara if a woman and Israel if a man. This law became effective January 1, 1939. These names were to be used on all correspondence -- private or official -- including return addresses on mail. This is a combined Israel/Sara registered envelope.https://digital.kenyon.edu/bulmash/1978/thumbnail.jp