(ROLEX without the O) N, C, & S came out during the early to mid 1990’s, W, T & U a little later.
** In 1987, rather than begin an 8 digit production serial, Rolex instead began their serials with a letter prefix such as R, then L, E & X. * We have seen G serialed watches that were produced in 2012, so Rolex is using both the mixed and the G at the same time.
