Bidspirit auction | Worldwide Air Post Stamps and

Worldwide Air Post Stamps and Postal History - United States - Air Post stamps - 1976, Plane, Globes and Flag, (31c), supposes to be in red blue and black, all colors omitted, bottom right corner sheet margin block of four, top right stamp with pencil shading, full OG, NH, VF and scarce multiple, PSE certificate, Est. $250-$300, Scott #C90b