This might help to determine a wrap's thickness:
|up to 180 g/m2||very thin|
|300 g/m2 and up||very thick|
Please remember this classification was made up by me, so it might be rather subjective. Also, different fibers have different density and weight. E.g. silk is lighter than linen, so a silk wrap of the same weight as a linen wrap might still be thicker.
The weight per square meter is calculated like this: total weight in grams divided by (total length along one rail in m x total width in m).