--Main parts are made of silicon;
--Aspirator valve is equipped with the fish mouth shape valve, which will close during respiration to avoid occurring flow backwards;
--Be equipped with the pressure limit valve avoiding the higher pressure output;
--The device is composed of Air bag, Aspirator valve, Collection air bag, Mask, Fish mouth shape valve;
--With three models: HF-I (suit for neonate or infant under 2 years);HF-II (suit for 2-7 years old children);HF-III (suit for adult).