One or more Dimension details for each of the Evaluation Samples are displayed in this table. These dimension values can be selected in the Size Chart > TDS tab. You can also select a new Dimension value for an Evaluation Sample on this tab. 

Edit the tolerance level details in the Tol (+) and Tol (-) columns for each of the Dimension values.

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Refer Evaluation Samples section on the Size Chart > TDS tab to understand how you can create one or more Evaluation Samples.