These washable exercise bands provide 100% comfort & durability. Reinforced stitching & anti-slip rubber layers. No rolling or pinching unlike some other resistance band sets. Our resistance hip bands are made of high quality cotton polyester stretch fabric material and built in elastic nature latex inner, so the fitness bands will never slide or roll up when you use. Not only thickened, anti-slip and high resistant, but also skin-friendly durable and stable.