72-3x, WX249, 1972 U.S. Christmas Seals Sheet, pm B, full gum, F, MNH. Fresh, full gum, shipped flat. Scan is of front of sheet.
Issued 1972 by the National Tuberculosis and Respiratory Disease Association (NTRDA). Designed by Linda Layman. Ten different winter and Christmas designs. Sheet of 100 (10x10) seals, SE3S, perforated margin at top, multicolored. Seal size: 27x19mm, perf 11. Printer's Mark B on seal #56 indicates I.S. Berlin Press. Vertical perfs cross margin.
This is mint, never hinged, full gum dealer stock.
Christmas Seals are also known as TB Charity Seals, and are usually classified as Charity Seals, or Cinderella Stamps.