Berkey Black Berkey Purification Elements, Pack of 2 Includes: Two Replacement Filters , Beware of Unauthorized sellers, be sure to buy from an authorized seller. Capacity: 6000 Gallons Cleanable, Self-Sterilizing Filters Each black element has a life of 3,000 gallons, or 6,000 gallons for the pair. (less than 2 cents per gallon of water). Original factory replacement element for all Berkey water filter systems.