Weights are used to verify the accuracy of the balance. There may be people who do not know, but the creatures of the scales also depend on the location of the scales. The force of gravity of the Earth varies depending on its geographical coordinates. Changing a little, but changing. Therefore, the scales that show, let’s definitely take in Korea - to bring them to Latvia will be a reading error. This error can be noticed only on professional high-precision scales. Of course, many other factors can also cause weights. Weights are used to adjust the balance or to control the accuracy of the balance. Weights are divided into classes depending on their permissible error relative to the standard. There is a table in which the permissible error is indicated for weights of each class for weights that differ from standard ones. Caution should be exercised when working with high-end weights. The use of tweezers is a prerequisite, using gloves only for higher weights. E2; F1; F2; M1: M2; M3. Tolerances for each weight in each weight category are given in the appendix below. Individual weights can be ordered in plastic or wooden cases, with or without calibration certificates.