9001V and 9002V only wear different ways? the size of the quality are the same<br />9001V for ear straps? easy to wear and pick off<br />9002V for the headband models? better comfort? suitable for long-term use<br />Function: can be used for some non-oily particles of respiratory protection? such as dust? dust? pollen? all kinds of productive dust and no volatile fog and other air pollutants can be used as environmental air pollution fine particulate matter (PM2.5) The basic protection