https://www.fysensi.com/products/flat-ear-loop/ Flat Ear Loop Ear loop for surgical face masks is made of spandex and polyester fibers. The Overview of Flat Ear Loop Flat ear loop for surgical face masks are made of spandex and polyester fibers. There are No chemicals are added in the process. The frequently-used width of our flat elastic band are 3.0MM-5.0MM, the specification can be customized in accordance to client requirements. Our flat ear band are in most cases used in the manufacturing of disposable face masks, children's face masks, medical disposable masks, surgical protective masks.