Letter from St. Thomas 17 December 1906 to Esbjerg, Denmark. A single, two pairs and a 3-strip 5 BIT green I. printing King Christian IX canceled with LAP 'ST. THOMAS 17/12 1906', plate flaw on lower right pair, with coloured dot below '5' on the right stamp. UPU letter rate 40 BIT from 15.7.1905 – (to Denmark) 30.9.1907, on 1.10.1907 Denmark rate was lowered to 30.9.1909, wheras UPU rate remained 40 BIT until 1.10.1909.