Black wool (gabardine-ish) apron skirt from robe de chambre line (c. 1990s, tag faded). Essentially a large rectangle with self-fabric ties at each end, skirt is designed to be wrapped around wearer's body then cinched in place. Smallish self-fabric ruffle running along hem differentiates skirt from others encountered in this style.

No size (womens/unisex)
Check measurements to confirm fit
All measurements

Waist (circumference): up to 84 cm (with comfortable overlap)
Hip width: 45 cm
Total width (flat): 130.5 cm
Total length (flat): 95 cm
Hem width (when folded over): 48 cm

Likely 100% wool (tags cut)
Made in japan
Circa 1990s (tags cut)