The Leeward Islands, like Mauritius, made use of the Key and Duty Plate method of printing stamps, but, unlike Mauritius, the Leeward Islands used both the small General Key Type and the larger High Value Key Type.
The small General Key Type has a Key Plate carrying the whole of the design with a blank panel at the top of the stamp to receive the name of the colony, and a blank tablet at the bottom of the stamp to receive the individual duty or value. In addition to the Key Plate, therefore, each duty has its own "Name and Value Plate". Each 'set' was of 120 impressions arranged in two panes of 60, in 10 rows of 6. The Plate number of the Key Plate is above the 2nd stamp of the left pane, and below the penultimate stamps of the right pane. On the two occasions where the Duty Plate was numbered, the number was above the first stamp of the left pane and below the last stamp of the right pane.