It’s a zabuton made of igusa (rush grass), which is known as a material for tatami or goza mats. The woven igusa cloth is less likely to cling to the skin and it can absorb and release perspiration quickly, so it is often used for a summer zabuton. Igusa (rush grass) has a pleasant flavor and known as a material having an aromatherapy effects. In haiku, “izabuton” is used as a kigo (a seasonal term) of summer.
[A Precaution for Use]
Don’t wipe clean with a damp cloth, because it may cause discoloration. Make sure to wipe clean with a dry cloth. Also, dry in shade.