29-4x, WX50, 1929 Christmas Seals Sheet0, full gum, F, MNH. Fresh, never folded, shipped flat.
Issued 1929 by the National Tuberculosis Association (NTA). Designed by George V. Curtis. Bell ringer design. Sheet of 100 (10x10) seals, blue, red, and yellow. Seal size: 18x23mm, perf. 12-1/2. Printer's Mark: a blue dot to right of lower right corner of seal #100, which indicates R.E. Heywood Company, Inc.
Christmas Seals are also known as TB Charity Seals, and are usually classified as Charity Seals, or Cinderella Stamps.