The major challenge of the future in the area of special flat glass is seen as the flexible availability of glass substrates which can be produced to a high standard of quality yet at favourable cost. Bigger; flatter, fault free, universally available from ultra-thin to ultra-thick, as inert as possible and able to withstand the rigours of processing in the widest range of demanding technical applications is the comprehensive requirement of modern special flat glasses. Schott's borosilicate float glasses have all the necessary prerequisites to meet these continually and rapidly growing needs.