Phresh FiltersPhresh Filters Phresh Carbon Filters are packed with APEX 4 8 virgin activated carbon. Specially selected for its grain size and quality, the carbons density optimises airflow and absorption power. The granular shape of the carbon is half the weight of pelletised carbon, making the filter lighter and easier to handle. Phresh does not compromise on the density of its carbon it is machine packed tightly into the carbon bed to reduce movement. The