This item is known in the catalogues as one of the following numbers:
Michel: 5 B x (parchment half thick or thin paper) or 5 B y (normal thick, half thick or thin paper) or 5 B z (horizontally ripped paper);
Yvert & Tellier: 8 (thick paper) or 8a (thin paper) or 8b (ripped paper);
Stanley Gibbons: 8 (thick or thin normal paper) or 8a (ripped paper);
OBP: 8 or 8a (thin parchmentish paper) or 8A or 8Aa or 8Ab (thick paper) or 8B (horizontally or vertically ripped paper).