Stampless 'On His Majesty's Service' economy envelope with fine strike of FIELD POST OFFICE D.41 cds of the 6th Division located in BELFAST dated 23 FEB 1922 (just six days after the issue of the first Irish stamps). Addressed to 'Supt No. 1 Remount Depot, Island Bridge, Dublin' with circular 'COMMAND PAY OFFICE DUBLIN' arrival cachet in red on front. Fine & rare.