This box is designed to define the desired composition of the glass. It consists of combo boxes to select glass components and text boxes to type the percentage for each component. The type of percentage is set up by the Mol.%/Wt.% option buttons.
By default the Calculator contains five pairs of fields to select components and type their concentrations. In the case more components need to be added, click on Add components. The number of components to be added by a single click on this button must be typed in the text box below the button.