Standard elements are suitable for all particulate removal applications in non-corrosive gases. The coarsest grade that will adequately protect the application should be chosen, as this will result in the most economical solution to the contamination problem.
https://www.headlinefilters.com/library/documents/25-64-70.pdf
https://www.headlinefilters.com/library/documents/12-57-50.pdf
https://headlinefilters.com/cdn/shop/files/12-32-50c.pdf?v=14766198858629861387