Exemption scope narrowed: denim and certain multicolour three- or four-thread twill fabrics excluded from relief. The exemption is clarified to exclude fabrics commonly known as denim and fabrics of yarns of different colours woven as three- or four-thread twill (including broken twill and warp-faced types) where the warp yarns are of one colour and the weft yarns are unbleached, bleached, dyed grey, or dyed a lighter shade of the warp colour.