Whether the mask should be semicolon and have metal parts

Semicolon type: If the protective mask has a different size, people with small or large faces may easily fit the mask.

No metal parts are used: Most nose masks of protective masks are made of metal, and many masks use nails to secure the headband. In some special application environments (such as radioactive aerosols), metal parts may be used when disposing of masks Will increase the difficulty of processing. Some polymer materials can be used for nose clips, and the headband can be fixed to the mask by welding, but it may increase the cost of the mask.