1923 ½d, horiz. strip of 4 on "First Day Cover"

1923 watermark "Se" ½d green hoizontal strip of 4, correct franking on a small cover from Dublin to Essex, cancelled 20 AP 23, the day of issue of the ½d. Enclosed is a small, embossed Governmenet Stationery sheet with a pair of the ½d affixed and bearing a purple CDS STAMPING DEPARTMENT / INLAND REVENUE / DUBLIN / 20 APR / 1923. Hib. D1 FDC.
Despite creasing and other small faults, an Exhibtion item of the greatest rarity.