Kent collar
The Kent collar is the classic and most widespread form of turn-down collar, especially on men's shirts. The collar is medium height and the tips are medium length compared to other shirt collars.
The Kent collar originated in the 1930s and goes back to George, 1st Duke of Kent . The Duke is said to have been looking for a way to wear a large tie knot (like the double Windsor knot that was popular at the time ) without feeling cramped.
One variant is the New Kent collar , a mixture of the shark and Kent collar shape.