Bissell Style 7 Vacuum Bag, 32120 This is an O.E.M. Authorized part Fits various Bissell models Oem part number 32120 This is a Bissell replacement part Part Number 32120 This is an O.E.M. part Includes 3 bags Works with Model #s: 3522 Series, 3545 Series, 3550 Series, 3554 Series When do I replace my Bag? For best cleaning performance, it is suggested to change your bag when it is 1/2 to 2/3 full. When accumulated, small dust particles can keep the air from circulating, which can reduce the suction in your vacuum