The model No. RFC-BBS radial flow granular carbon cartridge reduces chlorine taste and odor, bad taste and odor, sediment, rust, scale, dirt, coarse sand. 25 micron (nominal) filtration. Radial-flow carbon design, high flow rate capabilities. Filter life up to 3 months or 5000 gallon. Use with Model No. HD-950A (SKU 432660) filter.