Perrin & Rowe developed and patented the first 3-in-1 filtration tap over 40 years ago. The Southbank 3-in-1 Filtration Tap combines engineering finesse with Mid-Century style. Perrin & Rowe’s filtration system is one of the highest performing available, using a four-stage process to remove microscopic impurities, including bacteria, chlorine and other harmful organic contaminants. Yet it is simple to maintain – just replace the cartridge every six months.