Select your Berkey water filter, Berkey water purification system, Berkey water treatment system, and Berkey replacement water filter below. Email support@waterfilters.net if you cannot find your Berkey water filters or Berkey replacement filter below. These filtration systems are also known as British Berkefeld: Travel Berkey: 1.5 Gallon System, ideal for 1-3 people Big Berkey: 2.25 Gallon System, ideal for 1-4 people Royal Berkey: 3.25 Gallon System, ideal for 2-5 people Imperial Berkey: 4.5 Gallon System, ideal for 4-8+ people Berkey Black: 2 Pack of gravity filter water purification elements