"This Recommended Standard defines the method for establishing the relationship between the inside face panel edge geometry and the minimum published screen dimensions for shadow-mask color TV picture tubes and color monitor tubes (as defined in the Worldwide Type Designation System ?C EIA Publication TEP-106-A). It may also be used to determine the minimum published screen dimensions for an established panel design. Use of this Standard will establish the standard minimum published screen dimensions. If a tube manufacturer desires a smaller screen size than the standard for a particular tube@ it must be specified in the registered data for that type. The method takes into account the refractive gain through the glass panel and provides a specific tolerance to allow for manufacturing variations. The object is to have the screen area lie entirely within the main inside faceplate contour of the panel. This will avoid ""g"" errors resulting from printing the screen into the heel radius."