These hydrometers conform to the accuracy requirements for ASTM hydrometers, and have their scales affixed using a clear eposy for increased durability. Each hydrometer is calibrated in a triple accredited ISO/IEC 17025:2005, A2LA accredited laboratory against equipment whose calibration is traceable to NIST. Individually packaged with a multi-language Statement of Accuracy indicating accuracy traceable to NIST.

Equivalent to H-B Instrument 618930300.