<p><b>Size Test:</b></p> <p>Please check the dimension before purchasing.</p> <p>Nose to chin length: 5.9 inches, Nose to rear: 13.9 inches</p> <p>The following are general guidelines based on the weight of 120lbs-200lbs. Please note that facial measurements can more accurately ensure proper wearing.</p> <p><b>Key Feature:</b></p> <p>The breathable, durable and comfortable nylon and spandex materials</p> <p>The adjustable nose clip and a velcro band to match your size</p> <p>Double air valve to breathe smoothly and keep the inside dry</p> <p>The replaceable filters of 5Layers protection</p> <p>The 95% activated carbon layer to filter out PM2.5</p> <p><b>Mask Specifications:</b></p> <p>Type: Quick Dry, Windproof, Dust-proof</p> <p>Size: One Size</p> <p>Theme: Outdoor</p> <p>Material: Nylon and Spandex</p> <p>Season: Spring, Summer, Autumn, Fall, Winter, Year-round</p> <p><b>Package contains:</b></p> <p>1 x Dust mask (a filter included)</p> <p>6 x Filters</p> <p><b>The Steps to Replace the Filter:</b></p> <p>1. Unfold the dust masks</p> <p>2. Open the valves according to the "OPEN" direction</p> <p>3. Remove the filter and valve</p> <p>4. Replace the new filter, and then clockwise rotate the valve to fix the filter</p> <p><b>How to Wear Properly:</b></p> <p>1. Put the mask on the face, find the most suitable position between the bridge of the nose and the jaw.</p> <p>2. Fix the mask by the velcro band on the back of the neck.</p> <p>3. Adjust the nose clip to make it fit with your bridge of nose perfectly.</p>