[COMPATIBILE MODELS] The 115115 replacement True HEPA filter is perfectly compatible with for air cleaner models C535, 5300, 5300-2, 6300, 6300-2, P300, C535, AM90, 9000, 5000, 5000B, C909, 9800 Compared to Part for 115115 Size 21 Filter A [Why NEED CARBON PREFILTER] Without using the carbon pre-filter, its recommended to replace the Hepa filter every 6 to 8 months. But when used with carbon pre-filter it can extend the replacement time of the Hepa to 12 months. [TRUE HEPA FILTERS] The c535 Replacement Filter with true HEPA high efficiency filtration helps remove up to 99.97% of particles down to 0.3 Micrometre in size. [EASY TO USE REPLACE] Contains C535 True HEPA filters and carbon pre-filters.It is easy to replace and disposable, no tools required. Simply remove and replace from your machine unit when needed. Colour:White Black Material:filter cotton Package Contents: 3 x HEPA filters 3 x Carbon pre-filters Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.