Price is per pack.  This filter helps protect against a wide range of oil and non-oil based particulate contaminants. 3M’s Advanced Electret Media (AEM) provides a comfortable lightweight, easy-breathing combination. The 2091 is commonly used for welding, brazing, torch cutting, metal pouring and soldering. Inventory needs and training requirements of safety equipment are reduced because this filter works for many different applications. The filter is both flame and water resistant. Industries where this filter is commonly used include agriculture, construction, general manufacturing, pharmaceuticals and primary metals.