ITALY - Atlantic Base. 1943, double overprint 1 INVERTED on 30c Aeronautica, pair. O.g., never hinged. Very Fine. Cert Oliva, Raybaudi. Rarest value of the set. Sassone 18a; Euros24 000 (25 600 CHF). (Photo). Est. 5 000 - 6 000 CHF.