1. Aimcor Excel briquettes, manufactured by Applied Industrial Materials UK Limited at Newfield, County Durham, or manufactured by Oxbow Carbon & Minerals UK Limited, Windsor House, Cornwall Road, Harrogate, North Yorkshire, which—
(a)comprise petroleum coke (as to 60 to 75% of the total weight), low volatile coal and reactive coke (as to 20 to 25% of the total weight) and cold-setting resin binder (as to the remaining weight);
(b)were manufactured from those constituents by a process involving roll-pressing;
(c)are unmarked pillow-shaped briquettes;
(d)have an average weight of 73 grams per briquette; and
(e)have a sulphur content not exceeding 2% of the total weight.