Canada CL43a

1928 (March 9) (10c) Patricia Airways Limited, a superb corner mint example with intact rouletting on all sides and Series “20” number at top left, showing the striking INVERTED AIRPLANE ERROR and full pristine original gum. An appealing positional example of this very scarce error, Very Fine, Never Hinged (Unitrade CL43a; catalogue value $3,000)