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4 of Block Activated Carbon filters - 10" Big Blue Block Activated Carbon filters are similar in their performance to that of GAC filters, being made of fine coconut shell carbon they also do remove odors and tastes of many organic compounds, chlorine especially. Though, because this filters are made of a packed carbon (forming a cylinder block), they offer a much finer filtration of suspended particles and dirt.

Purenex 4C-10B Big Blue Whole House Water Filter Block 10-Inch 4 Pack of 5 Micron - B00N36DQC2