From spanx website: Flat out the most comfortable thinnovation around! This utra-thin mid-thigh fits like a second skin, combining comfortable smoothing with the flattest fit ever. But don't take our word for it...Trust Your Thinstincts! Ultra-thin microfiber comfortably firms rear, slims hips and smoothes thighs. Tummy panel flattens belly. Our flattest seams ever...for a bulge-free look on thighs! Cotton gusset for comfort—wear as underwear to eliminate VPL (Visible Panty Lines). Fabric Content: 53% Spandex/Elastane, 47% Nylon. Worn once for a wedding.