These are the best nose pieces I've found -- heavy enough to hold their shape and not need continual readjustment, but not weighty on your face. The curved ones are long enough to prevent fogging glasses (usually), but I didn't find the shorter, straight ones as useful.
Two issues: price (almost 50 cents each), and because of the firmness of the metal, it can be uncomfortable if the nose piece doesn't sit exactly flat to your face. That's a problem with the sewing of the mask, rather than the n...