These volumetric pipets are calibrated to deliver. Colour-coded. Marked A to certify that they meet the requirements for Type 1, Class A “serialized” apparatus of Federal Specification NNN-P-395. This is identical with the specifications for accuracy and design of N.B.S. Circular 602. Furnished with individual serial numbers. A Certificate of Graduation Accuracy is included. Each pipet is calibrated and certified against equipment whose calibration is traceable to NIST.