These pipettes are made from borosilicate glass in compliance with ASTM specification E-969. Color-coded. Individually serialized and certified. Calibrated to deliver. Printed with durable amber markings. Southern Labware provides Class A volumetric glassware that is manufactured to ASTM standards using state of the art manufacturing and calibration equipment. The calibration laboratory is NABL accredited in accordance with ISO 17025:2005 standards. Our Class A volumetric glassware comply with USP (United States Pharmacopia) standards.