Electrostatic charged fibers that retain dust and pollen down to 0.1 microns. A must for allergy sufferers. 7 Bags per package. Fits Royal: Ultra MVP Upright 360, 361, 380, 381, 655, 7500, 656, 7510, 670, 671, 7710, 672, 7720, 673, 7730, 690, 691, 692, 7920, 693, 7930, 885, 886, 886F, 994, 996, 6103, 6310F, 6800, 7700, 7900, 7910, 8801AE, 9100, 9700, TY7300 , RY7200, RY7300, RY7400, RY9700, RY9750 Eminence Uprights. Part#: 1116016000, 3115016000