This is a six-foot loincloth made of Hamatsumugi silk. It measures 36cm wide and 270cm long, and is made from fabric intended for kosode (short-sleeved kimono). It is sold in a longer length so you can cut and adjust it to fit your body.
Although new, it was made from vintage fabric, so there may be some age-related discoloration or stains.
*Hamatsumugi is a silk fabric (tsumugi) characterized by its soft texture. Produced by the Hamachirimen Industrial Cooperative Association. Because it uses leftover threads from Hamachirimen as the weft and untwisted raw silk as the warp, it combines the simplicity of tsumugi with the suppleness of crepe, and is known as a fabric favored by connoisseurs.