Environmental Protection Material: The earphone shell is made of environmentally friendly degradable non-woven material, breathable, soft, non-toxic, non-irritating, and does not cause ear allergies when in use. worn on headphones. Hygienic and Safe: These non-woven earmuffs help keep your headphones safe and hygienic, making public use of headphones safer and more hygienic, allowing you to share headphones with multiple people without sharing germs, lice or viruses. It is ideal for use in offices, internet cafes, hospitals and call centers. Won't Spoil Sound Quality: With great breathability and lightweight materials, they will not distort the sound quality. And protect your earphone pads from dirt, scratches and make your earphones look new. Extensible Helmet Covers: This set contains 200 pieces of 11cm diameter headphone covers with excellent stretch to fit most headphones with 3.93"-4.72" (10-12cm) ear cushions. Scope of application: 200 non-woven earphone sleeves are perfect for recording, working, aviation headphones, studying, singing, public hearings, public headphones in offices, libraries, hospitals, call centers , exhibition and museum kiosks and internet cafes.