1920. Prisioners of War Fund. 15 on 30 st chocolate, perf L 11 1/2. Very fine mint block of twelve from top left sheet corner, withFULL OFFSET of overprint at reverse, at front, majority of adhesives left WOITHOUT OVERPRINT, second to last vertical pair with PARTIAL OVERPRINT, and only the last vertical pair with FULL OVERPRINT, caused by a folded SHEET, resulting in an diagonal strike of the overprint at reverse. Absoluty spectacular error.