45NMp3, NTA 1945 U.S. Christmas Seals, Negative Makers Proof Sheet, F, No Gum. Issued 1945 by the National Tuberculosis Association (ALA). Negative Makers Proof sheet with wide margin. sheet of 100 (10x10), SE4S, without printer's mark, perf 11 3/4, "DD" in margin (Strobridge).
Christmas Seals are also known as TB Charity Seals, and are usually classified as Charity Seals, or Cinderella Stamps.
