M21 (1) SG 277
Purple on lemon
Ordinary paper
Perf. 14
Harrison
September 1911
Rarity

M21 (2)
Greyish-purple on lemon
Ordinary paper
Perf. 14
Harrison
1911
Rarity

M21 (3)
Grey on lemon
Ordinary paper
Perf. 14
Harrison
Only a RPS or BPA certificate can validate authenticity
1911
Rarity

No image avialable

M21 (4)
Dull reddish-purple on lemon
Ordinary paper
Perf. 14
Harrison
1911
Rarity

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