Specification :
Nothing but coagulated rubber sheets, properly dried and smoked, can be used in making these grades; block, cuttings or other scrap or frothy sheets, weak, heated or burnt sheets, air-dried or smooth sheets not permissible.
Slight resinous matter ( rust) and slight amounts of dry mould on wrappers, bale surfaces and interior sheets, found at time of delivery will not be objected to.
Oxidized spots or streaks, weak, heated and burnt are not permissible.
The rubber must be dry, firm, free of blisters. Dirty packing, sand, and all other foreign matter is not permissible.