The grade must be produced under conditions wherein all processes are carefully and uniformly controlled. Each bale must be packed free of mould but very slight traces of dry mould on wrappers or bale surfaces adjacent to wrapper found at the time of delivery will not be objected to, provided there is no penetration of mould inside the bale. Oxidized spots of streaks, weak, heated, under-cured, over-smoked, opaque and burnt sheets are not permissible. The rubber must be dry, clean, strong, sound and evenly smoked, and free from blemishes, specks, resinous matter (rust), blisters, sand, dirty packing and any other foreign matter. Small pin-head bubbles, if scattered, will not be objected to. No master or official international sample has been established for this grade.