The world's finest watercolor paint brushes were originally made for Queen Victoria by Royal Warrant in 1866. Series 7 derives it's name from her favourite size; the number 7. Only 5% of incoming hairs are deemed suitable for Series 7 production. Hairs are hand tied in the distinctive English "long belly" style at Winsor & Newton's east coast factory at Lowestoft, England. All brushes are wet tested before they leave the factory. Simply the finest brushes available!