The CP filter is a type of water filtration cartridge that combines two filtration technologies. The first part serves as a mechanical pre-filter that removes coarser impurities such as sand, rust, sludge and other suspended particles from the water. The second and main component is a block of compressed activated carbon, often referred to by the English term "carbon block". Activated carbon works on the principle of adsorption, a process by which chemicals are captured and retained on its extensive internal surface. In this way, the filter effectively removes chlorine and its compounds from the water, which often cause unpleasant taste and odour. It also binds organic substances such as pesticides, herbicides or industrial by-products. The filter does not primarily affect the hardness of the water, i.e. it does not remove dissolved minerals such as calcium and magnesium. Its main purpose is to improve the sensory properties of the water, i.e. its taste and smell, and to remove specific chemical pollutants.