The Moldex 4300 Airwave respirator features a patented design which allows for easier breathing by expanding and contracting with your breath. The Airwave even has less breath resistance than valved respirators. The Airwave incorporates a Dura-Mesh shell which keeps the filter cleaner, and helps the respirator hold its shape longer. The result is a respirator that lasts. The 4300 contains the P95 filter which can be used for both dust and oil-based particulates.