This inbound 1945 registered First Day Cover (FDC) from Denmark features a violet straight-line U.S. Customs Passed Free Chicago P.O. and bears a 10 cent postage due stamp with violet straight line Collect 10c Postage Due For Customs Service. The cover originates from Denmark franked with #312 Block Registered from Virum with label. A very colorful and unusual postage due item. It is a European Size envelope.