These microcapillary pipets are calibrated 'To Contain' and are 5 inches long with a single black capacity ring. They are color-coded for easy selection of the correct size. Clean and ready to use. Made of soda lime glass in compliance with ASTM Specification E438, Type II glass requirements. Packaged in easy-open cylinders for convenient dispensing. Designed from ASTM Specification E672 requirements.