Anti-bacterial Three-layer Mask is a medical mask consisting of an inner, middle and outer layer, with a middle layer of filter screen that can block particles of 5 microns (1 millionth of a meter) or more. Wearing Instructions 1. Take out the mouth mask and hang the ear straps on both ears. 2. Adjust the bridge of the nose. 3. Smooth the two sides of the mask so that it fits the face. Matters Needing Attention 1. This product is for one-time use, unpack it when used, and destroy it after use. 2. This product is recommended to be replaced every 2-4 hours. 3. Refer to the instructions for use before use. 4. Use with caution if you are allergic to non-woven fabrics or have abnormal cardiopulmonary function. 5. Store out of reach of infants and young children.Surgical Mask suppliers website:http://www.aphismask.com/surgical-mask/