Hook and eye
Name: hook and eye
Form: buckle on the collar of the uniform, commonly known as collar button.
The origin of the name: buckle the collar button to look neat and serious, so it is called the discipline button
Function and use: show etiquette and discipline.
Clothing carriers: uniforms, Zhongshan suits, military uniforms.
Material: copper.
Color: silver, black, gold, bronze, etc