Good used with a red MX and the scarce marginal vertical watermark guideline on the right (visible in final photo). Verified and guaranteed to be Plate 9. The vertical line watermark variation is described in the SG QV Specialised catalogue as being only occasionally seen on marginal s.Tamps (such as this one). The item "QV 1840 Penny Black Pl9 I-L / Vertical Line Watermark Variety" is in sale since Friday, November 1, 2019. This item is in the category "Stamps\Great Britain\Victoria". The seller is "englishdv" and is located in Rancho Palos Verdes, California. This item can be shipped worldwide.