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