FCP = Fluorescent coated paper PVAD = Polyvinyl alcohol acetate dextrin gum
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nd14

ND14 - Northern Ireland 5.5p deep violet, FCP/PVAD, two 4.75mm screen 150 phosphor bands (Cyl 1) (Harrison/photo) - Deegam N55.1.1 - S.G specialised XN28 - Stoneham U29 - Concise NI19

Two 4.75mm phosphor bands from cylinder 1 [23.1.74]
nd16

ND16 - Northern Ireland 5.5p deep violet, FCP/PVAD, 4mm screen 150 phosphor centre band (Cyl 1) (Harrison/photo) - Deegam N55.2.1 - S.G specialised XN29 - Stoneham U30 - Concise NI20

4mm phosphor centre band from cylinder 1 [21.5.75]