During games such as Left4Dead2 there comes a time when hiding in a porta potty becomes a final option to staying alive longer. The shitter shield can provide both safety and relief from many infected attacks such as incoming cars, logs, and dumpster bins. If the shitter door remains intact you are protected from bile, acid spit, and many claw type attacks.
Holy shit guys the tank has a car incoming! Charles head for the Shitter Shield!