The TL450 box comes with 100 trash liners per box. These liners are design to be changed out quickly and easily. Simply lift the outer retainer ring off the TH450 holder base. Then remove the full bag by pulling it down through the bottom of the base. Slip a new bag in from the top and fold about 2" of the bags top edge over the base. Snap the retainer ring back onto the hold it is ready to use. The bags are clear in color so you can see at a glance when they might need to be changed out.