S9 is a very good invention during this time of pandemic and will be a life saver for doctors
A very cost effective mask and the process of sterile and re using it is making it effective. It covers nose and mouth fully and unlike other masks, breathability is not an issue.
It is easy to clean and the availability of 12 filters with the kit makes the product a long term use.
The adjustable silicon band makes it possible to fit any face size which gives extra protection and safety.