This is BULK CASE LOT purchase of 50 total 6 quart microfiltration vacuum bags for the Sandia 6 quart backpacks. Save BIG off retail price when purchasing bulk. These bags Fit the following Sandia Plastics XP-3 Whisper 6 WERK.20 models; 74-2012, 74-2016, 74-2018, 74-2032, 74-2036, 74-2038, and also fits the Sandia XP-3 Whisper 6 HAUS models; 74-4001, 74-4003, and the XP-3 Whisper 6 Turbo models; 74-5001, 74-5003