With the filter discount package you have enough filters for a year of use of your AquaTru. The package contains 2 pre-carbon filters (1-2) and 1 VOC carbon filter (4), specially designed for AquaTru Carafe. The pre-carbon filter should be replaced every six months and is responsible for removing bacteria, sediment and other large particles. The activated carbon also removes any chlorine taste from the water. This prevents your device from getting clogged. The VOC carbon filter has been developed to remove the last impurities from the water, improve the taste and make the water suitable for consumption. The result is fresh and delicious filtered water. With this package, you have enough supplies for a whole year.