The great design called Iris is very clear on this fabric!
Jess and Jane is using a very travel friendly fabric that is 95% polyester and 5% spandex called ITY or Interlock Twist Yarn. ITY is a cool and fluid knit fabric with incredible drape due partly to the weight. This is a simple pull on tunic with 3/4 sleeves. Feels silky and doesn't wrinkle. It's great for travel or any time you want to be wrinkle free.
Made in the USA.