Until 1970 it was common for Irish stamps to be printed in sheets of 120 with a gutter pane dividing the two groups of 60 stamps. A Gutter Pair comprises one stamp from each of the top and bottom panes and includes the gutter margin between each stamp. After 1970 few stamp sheets had gutters except for 6th definitive series between 1980 and 1990 and a few select commemorative stamps.