The contraption on the 9211 is the one-way exhale valve. It's a simple flexible flap. With an exhale valve, the mask won't protect other people from an infected wearer because when they exhale, droplets can go out the valve. But to protect the wearer, they're supposed to be identical protection.

If you haven't worn one for an extended period, the exhale valve makes a huge difference over the normal mask. I'd compare wearing a N95 to breathing through a maxi-pad or a water filter. When it's properly fitted, it's hard enough to inhale. You shouldn't need to struggle to breath out as well unless you have to.