The Replacement Small Cartridge Filter Retainer (Shop-Vac 90526) is for use with Shop-Vac Small Cartridge Filters measuring approximately 5.75 inch diameter and 5 inches high. For use on: 4 Gallon Floormaster, All Around Plus (not All Around), 5 Gallon Heavy Duty Portable, and Hang Up Vacs (not the Industrial Hang Up Vac). The Small Foam Filter Sleeve (Shop-Vac 3183000) can be used for picking up wet messes when used alone. It can also be used for dry pick up when used with a disposable filter bag. The Foam Filter Sleeve is required unless you are using a cartridge filter. Filter sleeve fits: Shop-Vac 1-4 Gallon wet dry vacuums (except models J200A, K250, KA450, L250, MACM-250, MACS-200D, MC150A, MC12V1800, 1x1, Micro, HangOn, HangUp Mini, All Around, All Around Ez), 5 Gallon portable model H87S, 5 Gallon HangUp, 5 Gallon Wall Mount and 6 Gallon long life model P12S vacuums.