Calibration Weights are used to check the reading of scale, to make sure it is still accurate. They used when calibrating a scale.
While the calibration states how a scale behaves, adjustment of the scale changes its behavior. What it dose is a set of operations carried out on a scale so that it provides prescribed indications corresponding to given values of a quantity to be measured.
Therefore, adjusting a scale means modifying its indications in a way that allows them to correspond – as much as possible – to the quantity values of the measurement standards applied.
ANSI/ASTM Class 1 Calibration Weights - Can be used as a reference standard in calibrating other calibration weights and is appropriate for calibrating high-precision analytical balances with a readability as low as 0.1 mg to 0.01 mg. ASTM Class 1 calibration weights and calibration weight set classes should be used in pharma quality control, research and development, analytical testing, chemical manufacturing, or other similar weight calibration environments. Class 1 weights can be used to calibrate analytical balances, Class I and Class II laboratory balances, and ASTM Class 4, 5, and 6 weights. Class 1 weights are equivalent to OIML Class E2 weights.