SEBO X Series Bags are in a 8 pack. These are their synthetic bags that allows for better suction as well as a HEPA certified material. The part number is 5093AM. SEBO X Series Filter Bags work with X, C, 370, and G Series Vacuums. Topfill, three, and fourlayer bags are an integral part of SEBO’s filtration system because they hold virtually all dirt captured by the vacuum, which improves the effectiveness and useful life of the microfilters. They also ensure continuously strong suction because dirt enters from the top, deposits at the bottom, accumulates upward, and air exits through the sides, which allows unimpeded airflow as they fill to capacity. And they can be sealed when full, so no dust can escape into the air during bag removal and disposal.