Fabric type 55.1% Nylon, 27.7% Polyester, 17.2% Spandex.Care instructions Machine Wash. .Closure type Elastic.COOL AND BREATHABLE: Our cooling skull caps is the effective solution for keeping your head cool and comfortable in the summer heat. The mesh fabric design ensures optimal air circulation, keeping your head cool and refreshed even after a long day of riding or working in the sun. It's especially good at keeping the cool feeling for hours after getting wet..SWEATING ISN'T A PROBLEM: This sweat wicking skull caps is ideal for anyone who loves to be active and sweat, whether it's intense outdoor exercise or working out in the sun. It quickly absorbs sweat and dries fast, keeping your head fresh and dry so you can focus on the task at hand and stay comfortable all day long! This sweat cap between helmet and hair absorbs moisture to maintain the cleanliness of the helmet and extend its life..FITS UNDER HELMET: Our helmet liner is the choice for anyone looking for a soft, comfortable, and skin- under helmet skull cap . It's so thin and light that you can wear it on your head like you're wearing nothing at all! It's for wearing under various types of helmets, such as hard hats , bicycle helmets, motorcycle helmets, and so on..HIGH STRETCH FOR EVERYONE: With excellent elasticity, our hard hat liner can flexibly fit different head sizes in one size, whether you are male or female, big head or small head, and can be easily worn to ensure a comfortable fit without being too tight. Plus, the depth of the hat is increased so that it sits more firmly on the head and does not slip easily..VERSATILE AND STYLISH: This summer skull caps is for a variety of outdoor activities, like cycling, motorcycling, running, climbing, and hiking. It's also a accessory for everyday outdoor work. Whether it's sweat absorption, cooling, sun protection, or prevent unpleasant smells it can do the job in a flexible and convenient way. It's also small, lightweight, and easy to carry, so you can take it with you anywhere.