The two upper corners hold Maltese crosses with radiant solar discs at their centres; the lower corner letters show the position of the stamp in the printed sheet, from "A A" at top left to "T L" at bottom right. The sheets, printed by Perkins Bacon, consisted of 240 stamps in 20 rows of 12 columns. One full sheet cost 240 pence or one pound; one row of 12 stamps cost a shilling. As the name suggests, the stamp was printed in black ink. A two penny stamp printed in blue and covering the double-letter rate (up to ) was issued on 8 May 1840.