79% nylon, 20% elastane, 1% cotton. Machine wash cold in laundry bag, dry flat.
What I love about these is they give support for the whole abdomen (unlike a belly band in my case since my torso is quite long). I've been having some recovery issues with abdominal muscle strain post c-section and these really hold me in nicely and help me be more active again. They stay up great and have given me so much back pain relief. They smooth everything out and even help with posture. Amazing.