You are getting 5 per order.Ship From Pennsylvania, USA In hot and humid working environment with poor ventilation or heavy labor, the use of mask with breathing valves can help you feel more comfortable when exhaling Add to a pre existing mask by cutting a star shaped hole, then pressing valve into fabric. Or use when making masks your self. The action principle of the breathing valve is to blow the valve plate open under the positive pressure of the exhaust gas when exhaling, so as to quickly exhaust the waste gas in the body and reduce the sense of stuffy heat when using the mask, and the negative pressure will automatically close the valve when inhaling, which can avoid inhaling the pollutants from the external environment, RETURN POLICY The buyer is responsible for paying return shipping cost. Please contact us to return your item within 14 days from the date that you received your item. The items that have been opened, worn, used, NOT accepted.