Lace up once and never tie again, no extra hardware needed Adjust customized tension between each eyelet for different feet shapes Outer Material: 77% nylon, 11% rubber, 10% Silicon, 2% Acetate Closure: Pull On Elasticity allows shoes to expand and contract with natural feet movements Avoid pressue points caused by knots or plastic hardware Transform shoes into slip ons while keeping consistent tension Caterpy Laces are the world’s top selling no tie shoelaces. They use elastic bump technology to hold customized tension throughout all eyelets. Invented in Japan by a marathon runner, Caterpy Laces strives to solve all shoelace issues. These issues include inconsistency of tension throughout the shoe, lack of adaptivity for different foot shapes, and inconvenience of tying laces. Often times, people think foot pains develop from an improper shoe, when it may be from improper laces. Although Caterpy Laces are designed for athletic wear, the product is popular among other users including kids, elderly, medical, and individuals with special needs. They’re the perfect fit from joes to pros!