What's the fourth-level knife of China Wushu?

Four-ring knife. China Wushu Level-4 Knife is a kind of four-ring knife, which is a traditional sport in China, and is a technique of martial arts, boxing and weapon use in China. People in Guangdong and Guangxi called it Kung Fu, and in the early Republic of China it was called national martial arts, which was regarded as the essence of Chinese culture, so it was also called "national quintessence". Wushu refers to China Wushu, and there is no such name for fighting in other countries. China Wushu can also be divided into narrow sense and broad sense.