Density standards can be used as calibration standards for density measurement by pycnometric techniques, vibrational techniques, or hydrometer-based techniques. These standards are prepared gravimetrically (solute and solvent) using OIML traceable weights. The density of the standards is established using fully calibrated reference pycnometers. Density standards are highly accurate and can be used with any brand or type of density-measuring instrument. Standards are presented in a high-quality tamperproof amber glass bottle.