Kelantan's D is a straight, narrow lane.

The state's early KN mark is replaced with D in 1948 and, unlike some others, that is the last major change. Registrations grow, but not in sudden spikes; Kelantan only needs the three-letter format in 1995.

Because of that, the D-series feels self-contained. It has one clear conversion (KN to D), a long run in the classic format, and a late, orderly step into the modern one. There is no drama in its history—and that predictability is exactly what gives the prefix its character.