Mingzha means "name tag, name card, name tag".
The name book generally shows the individual's name, school name, and school badge, and is pinned to the chest. Many people wearing JK uniforms can make Mingzha.
JK is a Japanese buzzword, meaning high school girl uniform (じょしこうこうせい). Take the J and K in the Japanese romanized jyoshikoukousei. There are many types of JK uniforms, and if they are broken down, there are very many styles. Including sundresses, summer clothes, mid-range clothes, vests, suits, coats, winter clothes, cardigans, sweaters, shirts and more.