1:Suitable scenario:Suitable for work, home, car, outdoor, hospital, school, restaurant, sports, or any other occasions2:Suitable Professions: nurses, doctors, teachers, waiters, bartenders, workers, security, police, and all other occupations you can think of3:Very convenient and clean: Don't risk putting the mask on the table or in your pocket to avoid staining the mask. No need to worry about the mask being thrown away when you eat and drink outside. Just put it down and it will hang on your chest4:Multi-purpose: suitable for most glasses, straw hat rope, work permit. The strap can also hang many things like keys, remote control5:Washable, can be reused6:Two options: 10 packs of mixed colors OR 10 packs of black7:Material: nylon/plastic buckle8:Do you need batteries? NO