The versatile Royal Berkey® system is the ideal system for use at home with large families, travel, outdoor activities or during unexpected emergencies. This powerful system purifies both treated water and untreated raw water from such sources as remote lakes, streams, stagnant ponds and water supplies in foreign countries, where regulations may be substandard at best. Perfect for outdoor activities and a must in hostile environments where electricity, water pressure or treated water may not be available. The Big Berkey® system removes pathogenic bacteria, cysts and parasites entirely and extracts harmful chemicals such as herbicides, pesticides, VOCs, organic solvents, radon 222 and trihalomethanes. It also reduces nitrates, nitrites and unhealthy minerals such as lead and mercury. This system is so powerful it can remove red food coloring from water without removing the beneficial minerals your body needs. Virtually no other system can duplicate this performance. Constructed of highly polished 304 stainless steel, the system comes complete with two purification elements and utilizes the latest technological advances. This system has a storage capacity of about 2.25 gallons (8.5 liters) and when in use it stands 19.25" in height with a diameter of 8.5". The upper chamber nests within the lower chamber for transport and stands only 13" in height. Configured with two Black Berkey® purification elements the system will purify up to 3 1/2 Gallons (13.3 liters) per hour*. This system can be expanded to use four purification elements and is capable of purifying up to 7 Gallons (26.5 liters) per hour*. *Flow rate calculated with upper chamber full to top. Flow rate decreases as water level declines.