1912 envelope to COSTA RICA, franked with a 4c, 3c, 1c and 2c, correctly paying the 10c rate, cancelled KUDAT 19 AUG 1912. A Singapore 25 AU 1912 transit cancel is on the back and a San Jose 8 OCT 1912 arrival c.d.s. is on the front of the cover. A very scarce destination for mail from North Borneo pre WWI.