The top buttonhole of the shirt is horizontal. There are two main aspects: on the one hand, the reason is very simple, it is for the sake of beauty; the second aspect is also the main reason, that is, from the perspective of durability, the horizontal buttonhole is pulled apart. The probability is also less than the longitudinal buttonholes. If all the longitudinal buttonholes are used, some areas with high force are likely to cause disengagement during deformation. Like the neck activity is relatively frequent, a stronger lateral button is needed.