74-1x, WX2b2, ALA National Design 1974 U.S. Christmas Seals Sheet, pm E, full gum, F, MNH. Fresh, full gum, shipped flat. Scan is of front of sheet.
Issued 1974 by the American Lung Association (ALA). Designed by Rubidoux E. Johnson. Images of children on sled, dog and cat, mailman, snowman with children, all alternating on the sheet. Sheet of 100 (10x10) seals, SE3S, perforated margin at top, multicolored. Seal size: 17x22mm, perf 12-1/2. Printer's Mark E on seal #56 indicates Eureka Speciality Printing Co. Vertical perfs stop at 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.