1907: Postage dues ½ d green with watermark inverted in a complete sheet of 120 stamps made up of two panes of 60 stamps united by gutter, ACSC no. D66, perfect condition and full original gum (only hing remnants at sheet margin), the sheet includes 12 examples showing part of the marginal letters in the watermark (ACSC no. D66aa), as well as one example of the plate flaw (ACSC no. D66d), only 100 sheets printed, most PROBABLY UNIQUE, as even single gutter pairs are virtually inexistent. (M) (Tax Method: Margin System)