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.
OIML Class E2 Reference 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. OIML Class E2 weights can be used to calibrate analytical balances Class I and Class II balances. OIML Class E2 weights are equivalent to ASTM Class 1 weights.