The 3M-502 allows you to attach a 3M-2091 Particulate filter to a 3M Vapor Cartridge. Suitable for use with the 5000 6000 and 7000 series respirators. This Adapter provides you with the ability to have complete Particualte protection and Organic Vapor protection---all with the same respirator body all at the same time with no need to change cartridges between sanding and painting.