1917-18 Red Cross 4c + 2c orange, horizontal pair (setting I, R1/5-6) left stamp showing varieties 'COMMA AFTER 2c' and right stamp 'SS INVERTED' with both stamps also showing repeated '2c.' at top. Fine og with the usual characteristic faintly toned gum. Very rare and a wonderful exhibition piece. SG 20a/b: Estimate £1000-£1200 (Image)