Flower pot 17.5x19.5 mm
Colour: Violet
Items known:
1.6.1965 Trollhättan 1 to Elkkart IN (US), violet

1.6.1965 Air mail letter, 5-10 grammes to USA. Surface postage 60 öre, air mail fee 25 öre/5 grammes; totally 110 öre. Shortpaid 50 öre. Amount due 2x50/1.70=59 centimes. The US Post Office has probably not noticed the due marking.