NSF Certified 4.5 Gallon (3.2 Draw-down) Reverse Osmosis Water Storage Tank. Lead, brass and copper are banned for use in purified/drinking water. This tank uses stainless steel connections to avoid lead leaching concerns. This tank is NSF approved under standard 58, and CE approved under the PED (pressure equipment directive). Features - Stainless steel connection - Smooth internal air vent cap prevents diaphragm damaged. - High-grade butyl diaphragm, post-cure procedure insures a tasteless and odorless water chamber - NSF 61 and 58 listed. - IAMPO approved. - CE Mark approved. Specifications & Dimensions - Actual tank size: 4.5 gallons - Tank storage capacity: 3.2 gallons. ** TANK BALL VALVE NOT INCLUDED**