SARS making almost everybody in Hong Kong equipped with mouth mask on the street. As I have been on mouth mask on most day time for the last 2 weeks, I earn more knowledge of these mouth mask. My current favorite becomes the "duck beak shaped" Kimberly-Clark PFR95 "N95 compliant" mask. The mask could be folded into a few papers' thickness when not in use. It comply with the N95 standard, meaning that 95% of the air particles could be filtered, which can keep you away from tuberculosis and even anthrax infection. Plus, when you wear it, you will look exactly like "Howard the Duck"!