Airmail cover from Centro de Importação Automobilista (C.I.A.L.), Coimbra, Portugal, addressed to Atlas Manufacturing Co., Indianapolis, Indiana. Printed letterhead advertises parts for Chevrolet, Ford, and Fiat. Reverse features four automotive brand advertisement panels including Atlas Parts for Chevrolet/Ford/Plymouth, Mareco Ignition Parts, Lyons, and Specialloid Pistons. Single 3$50 caravel stamp with Lisbon airmail transit on reverse. Corner tear, light creasing.