Kenbi mirai's "Silk Protein Belly Warmer" is made of a cotton blend material with a "silk protein" finish. The material has a natural moisturizing effect and is gentle to the body. Warm yet thin, this waist warmer can be used in all seasons, not only in the cold winter months, but also in the summer when air conditioning is a concern. The far-infrared rays of this belly warmer make it warm for both men and women, and ideal for keeping out the cold in winter. Although not intended for pregnant women, this belly band stretches well and is wide enough to be worn by women as well as maternity and men.