Here at GPE Scientific we supply borosilicate glass tubing from sizes 3.5mm – 152.4mm (6”) internal diameter. We are able to manufacture to extremely tight tolerances: Up to 35mm internal diameter ± 0.01mm, Over 35mm internal diameter ± 0.04% of bore. Our standard production length is 1000-1200mm. We can cut, grind and modify the borosilicate glass tubing into a variety of designs so please let us know your requirements.