Input-output norms govern component proportions and require importers to ensure imported items are used in export manufacture. Standard Input-Output Norms for outdoor Current Transformers above specified voltage list permissible input components and their proportions for one finished transformer, and require determination of the proportion of various inputs for different resultant products. Applicants must ensure imported goods correspond to the inputs actually used or required in the manufacture of the exported transformer; the SION is suspended by public notice.