Nylon. Underwire bra, made especially for nursing, t-shirt bra. Seamless light 4-way stretch pad, hand wash, b/c cups have 2 hooks with 4 adjustments. One-handed clasp helps easy nursing, d/dd cups have 3 hooks with 4 adjustments, Adjustable straps, 85% nylon, and 15% spandex. Back opening, cup lining is 100% nylon. This leading lady nursing bra provides slight padding and a seamless style.