The D304 2.25 G Gravity Water Filter System by Phoenix Gravity is a high-quality water filter that utilizes dual carbon filtration to provide clean and safe drinking water. This NSF/ANSI 42 certified filter is designed for easy installation and is compatible with the Aqua Optima Evolve model. With one filter included in the pack, this system is perfect for households looking to improve the taste and quality of their tap water.