The Adsorptive cartridge uses a core with two adsorptive materials. Activated clay is uniformly blended with activated carbon to provide some removal of oily contaminants in systems that lack distillation capability. Puritan filter cartridges are designed and constructed to trap and hold substantially more insoluble soil than competing brands. Up to one third more usable surface area than other brands, with more premium filter paper and precise, deep pleating Puritan's extra surface area holds more dirt and lasts longer.