Filters are with integrated mouthpiece or disposable mouthpiece (plastic or cardboard) and disposable nose clip
Custom-engineered plastic oval mouthpiece (optional) - prevention against slipperiness and stickiness - that is anatomically suitable with the mouth structure of adults and children
Minimum extra resistance except the acceptable filter pad resistance. Connection without intermediate adaptor to all leader spirometer devices
3M™ filtration media
The dead space is less than 75 ml
Liquid-tight to prevent liquid particles
Unopenable structure; streamlined, and stabilized sloped area to prevent pressure loss and other external factors during respiratory flow