Aiwd Water Filtration SystemThe FILTER282TWIN is commercially approved to NSF 169 standards. It is a two stage water filtration system for use with the AIWD282, AIWD160, or AIWD450. The first stage introduces an FDA approved treatment to control scale formation before entering the icemaker, which helps to prevent clogging and mechanical issues. The second stage is carbon filtration that improves the taste of the drinking water, ensuring that ice and water is clear Note: Upon