Sub-Zero 7023812 Refrigerator Carbon Block Water Filter
( For built-in Models prior to serial # 4116297)
Some municipalities and rural areas may have water conditions too severe for the Microbiological Water Filter, which may obstruct flow after a few months. In these rare instances, we recommend this carbon block filter. While this filter is not as robust as the Microbiological Filter, it will last 12 months under harsh water conditions.
IMPORTANT: only order this filter if your serial number is prior to 4116297.