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HMRC internal manual

VAT Clothing

The design test - is the article designed for young children?: Maximum Clothing Measurements

If your garment does not immediately pass the tests of VCLOTHING4100 and VCLOTHING4150, you will have to consider the concept of maximum measurements.

A table of maximum garment sizes is in Notice714. This table is based upon the size of an average child up to the eve of his or her fourteenth birthday, as set out in the relevant British Standard. These have been converted to a list of maximum garment measurements and sizes, taking into account the varying manufacturing tolerances required by the style of the garment, and whether it is to be worn over other garments.