Air Purifier Spares- Ceiling mounted - Filters To be changed every 3 months Price: £70.50 incVAT These filters create a powerful charge onto special media pads, which act like a magnet to attract and hold harmful, lung damaging airborne contaminants. This method is completely safe, remarkably efficient, crackle free and non-ozonating. Pack of four filters. To be used with the CM550B ceiling mounted air purifier.