1854 1d star die I plate 173 (RK)S.C.16 WATERMARK INVERTED ON COVER (SG 17Wi). 1854 envelope London to Rugby with fine example in State I lettered RK tied London '41' numeral. On reverse 'King William St' local receiver in blue and London datestamp 7/AP/1854 . Watermark inverted clearly seen when held up to the light. Very scarce usage. (Ref 49944).