I found this on internet but i don't understand all :

Pale crepe rubber is among the highest quality crepes. Coagulation of this high-quality natural rubber is achieved with sodium hydrogen sulfite (NaHSO3). The clean coagulum is washed and milled. This produces sheets between 1.2 and 1.5 mm thick and 24 cm wide. The washing process removes from the coagulum considerable amounts of the serum constituents which can cause rotting. The sheets are dried in drying rooms for 2.5 to 4 days at 37°C or air-dried for 5 to 10 days on drying floors.

Excessive temperatures lead to discolored patches in the sheets as a result of oxidation. The sheets are packed as bales and marketed as "thin pale crepe".

The 10-mm crepe from Sri Lanka is marketed as "thick pale crepe".

Two different types of sheets are distinguished:
ADS (air dried sheets)
Air dried sheets are less common. They have an appearance similar to RSS (ribbed smoked sheets), but are more transparent, as they are manufactured in smoke-free rooms.

RSS (ribbed smoked sheets) (see Figure 1)
The fresh latex is diluted to a rubber content of 15 - 16% and coagulated in coagulation tanks using formic acid or acetic acid. Lumps of coagulum are formed after the acid has acted for 3-4 hours. After milling and washing, sheets between 2.5 and 3.5 mm thick, 24 cm wide and 90 or 135 cm in length are produced. The final mill is an embossed mill, which gives the sheets their ribbed structure. Since these rubber sheets are not washed as intensively as crepes, they contain a higher proportion of serum constituents which encourage mold and rotting. For this reason, the sheets undergo an additional preservation process in which they are smoked in smokehouses. The sheets are hung in the smokehouses and dried for a week at temperatures up to 60°C. The smoke resulting from burning Hevea (rubber tree) wood and other organic materials such as coconut husks preserves the sheets. The specific smell of these sheets is caused by the materials used to produce the smoke. The sheets are pressed into bales and wrapped in protective sheets. The surface is protected from oxidation by application of a bale coating solution and talcum.

Can you tell me if there is a big différence between the two rubber.
If there is a big difference i must keep on searching and forget the ADS latex

Thank you in advance.