D

D

Denier

The thickness of a single strand of hair, usually specified as fine, normal, or coarse.

Density

The amount of hair ventilated in a hair system base. Refers to the overall thickness of the hair system (not individual hairs). Increasing density makes the hair system thicker; decreasing density makes it thinner.

Donor hair

Hair that is voluntarily donated by human beings to be used in making hair systems, wigs, and extensions.