The bottle containing Acuaiss Ultra Moisturizing Drops is designed to protect its contents from external contamination
The OSD bottle protects its contents from external microbes thanks to a filter that prevents contaminated air from coming into contact with the liquid inside. This is possible because the OSD system features separate circuits to let air into the bottle and let liquid out.
The liquid is dispensed through the dropper due to the pressure created when squeezing the bottle. Once the drop has formed, an inner device shuts the system to prevent microorganisms from entering through the dropper.
But the OSD bottle needs an air inlet in order to recover its shape. That air flows in through a side circuit that is physically separate from the liquid outlet, and passes through a sterilising filter.