N55 has been used all the time, and now Jin Chen and Chen Long use rackets, which belong to the single-pull and single-hanging assault type. N80 and n90 belong to the same type. The middle pole of n55 is relatively hard, not as heavy as the head of n90, but slightly heavier than the head of n80. The overall quality is the same, belonging to 3U85-89g. The swing weight is different because of the different head weight, which is related to the style of play and does not attack violently.