See YOO in 521days ^^v (Dec 12.2009)

Congrats to Private Monster Baby YOO to be First Class Soldier

http://en.wikipedia.org/wiki/Military_of_South_Korea

http://en.wikipedia.org/wiki/Military_ranks_of_South_Korea

http://en.wikipedia.org/wiki/Comparative_military_ranks_of_Korea

and this is a picture about Private First Class badges of South Korea.

for more detail....

http://www.globalsecurity.org/military/world/rok/army-uniform-1.htm