Australia 1966-73 Decimal currency 5c 'Yellow-tailed Thornbill', SG386/aAustralia 1966 73 Decimal currency 5c 'Yellow tailed Thornbill', SG386 a. An unmounted mint, with full original gum, horizontal strip of 5 with margins at left and right, the first stamp showing ERROR BROWN (plumage) OMITTED, with partial omission on the adjoining stamp. Spectacular and rare with about 25 reported in unused condition, and especially desirable in this se tenant form. Accompanied with a British Philatelic Association (BPA) certificate