The Tagua L is made of a natural seed which is called Tagua or vegetal Ivory and elastic. It is very adjustable,  you can stretch it depending on the size you need.
The dark color on the bracelet is the skin of the seed which gives it a natural looking.

The longest diameter of 9 1/2 inches

Tagua is a wild fruit, which grows in tropical forests in Colombia under the canopy of other trees which provide it with shade. It is almost impossible to reproduce the conditions and type of soil in which is able to grow, therefore, all tagua is harvested from wild sources. Due to its plant-based origin and its physical similarity to ivory, Tagua is a sustainable substitute for items traditionally made from the tusks and teeth of elephants and whales. This seed is collected from the soil, has a dye process, and after two weeks of drying it is ready for drilling and assembling the jewels.
-Because this product is made from Natural and unique seeds it may present some texture variations.