The one-way valve and directional diaphragm on the Ferno E-Mask allows no backflow of air or contaminants (fluids) to pass from the patient to rescuer/rescuer to patient and provides superior protection against viruses and bacteria. The Ferno E-Mask comes with an O2 port, headstrap and hard shell case. Fittings are a standard 22 mm and can be used with any Ferno resuscitator. The Ferno E-Mask fits both adult and child patients. Once used, the mask can be sterilised and a replacement one-way valve/filter can be fitted.