VCLOTHING2500 - How to decide if the article is clothing: Incomplete Articles
An unfinished article may be considered to be clothing provided it has been processed to such an extent that it could not reasonably be used for any other purpose - for example, cut-out parts of a garment or pleated skirt lengths. Such items would, of course, still have to pass the design and suitability tests in the same way as whole garments before they could be zero-rated.
This policy is a result of the High Court decision in the case of Ali Baba Tex (LON/89/270). Here the Court ruled that a pleated skirt length for incorporation into an eligible child’s skirt could itself be zero-rated.