The Pentek P-250 Under Sink Water Filter Set includes both a D-40 sediment filter (white cartridge with green end caps, for the left housing) and D-25 carbon filter (gray cartridge with black end caps, for the right housing). The carbon block ultra-fine filtration removes dirt, sand and other particles from your water, while also reducing unwanted chlorine taste and odor for a better drinking and cooking experience from your kitchen faucet. The P250 also filters mercury, volatile organic compounds (VOCs), herbicides and pesticides. This is a low-cost, convenient alternative to bottled water.