Here is a review left by a customer on a product. Would you say he was satisfied or dissatisfied?
Title: Breathe cleanly with this mask in very dusty environments
Review: This is the only mask that I will use for keeping the nasty dusts out of my lungs and sinuses. My wife MUST use this mask also as it prevents the molds from tripping her breathing problems. The outlet valve keeps the hot exhaust air going out of the mask.
