Par Avion is the visual language of mid-century international airmail: the UPU-standard PAR AVION etiquette, the red-and-blue barber-pole envelope edge, and featherweight onionskin paper tinted cool blue-white to shave postage weight. Ink is strictly cool — royal blue, postal vermilion, navy-black — never warm sepia.

Everything is engineered for lightness and legibility across borders: condensed caps for addressing, typewritten correspondence, circular and wavy-line cancellation postmarks, and a crisp gridded layout that never rounds its corners or softens its geometry.