GREAT BRITAIN 1968 (MNH) 7D BRIGHT EMERALD CYLINDER PH1 BLOCK
7d Bright Emerald, type B head, PVA gum, two phosphor bands, corner block x 20 with phosphor cylinder 'Ph1' in right margin (above punch hole). Difficult specialist item. Fresh and fine. Mint never hinged. SG737; SGU19; SCMH10
Note: phosphor cylinder 'Ph1' is found on cylinder 4. panes in the right margin. It is best viewed under ultraviolet light