Rolco watch. 1940's I think.

Any help with identifying what age this watch is would be most happily received! My uncle brought this watch as a present for my grandmother during the war or just after possibly. He bought it from Boodle and Dunthorne in Liverpool, UK. He was in the Navy during the war and must have been in port in Liverpool at the time as he lived in Swansea in Wales, UK. It has a petersham wristband and I think it's made of gold but not sure. Has numbers on the back 515 and 271711.