Specification: Ф2.2mm - Ф60mm,SiO2 ＿9.96%, it has good physical and chemical character such as resistance to high temperature, resistance to acid and alkali, also well known as stability under high temperature,insulating and good spectral transmission charater( ＿0% ), we can produce low OH tube(＿ppm or ＿ppm) under clients request.