help identifying my rolex present please

[duncan2011]

hi,
i recieved this rolex as a present but having trawled the internet for hours i can't seem to find the model anywhere ! i have seen some like it, dated around the 1950's but i would love to know more about it.
any help would be greatly appreciated.

here is the link as i can't seem to upload on the site yet.

http://s1111.photobucket.com/albums/...t=IMG_0940.jpg


many thanks