17c Black, "ZONE CANAL" & "ZONE" Only

B.L. Imprint Margin Se-tenant Pair with both the 91a and 91c varieties, OG, LH, the T. stamp has the "Zone Canal" variety of which there are 450 printed and the B. stamp has the "ZONE" only variety of which there are only 40 issued, in addition this stamp also has the broken "O" in "Zone", there are only four recorded exampes with this broken "O" variety, then to have both of the major varieties along with the broken "O" in a multiple is certainly a most unusual Showpiece item, (ENV 1,500-2,000)