Ferrite Core Noise Suppressor Filter Rings quality materials: Crafted from quality ferrite core material for durable, longlasting performance. noise cancellation: Specifically designed for USB, Firewire, Phone, Powerline, Coaxial, Audio, and Video cables; suppresses interference to deliver a clearer signal. Easy installation: Clipon rings attach quickly to cables with no tools or complicated setup. Versatile application: Suitable for use with computers, hard disks, audio equipment, copiers, fax machines, and more. Use scenarios: Improving USB or Firewire connections on a desktop or laptop to reduce interference and improve data stability. Reducing noise on audio, video, or coaxial cables in home theater or studio equipment for clearer playback. Suppressing EMI on office devices such as copiers, fax machines, and powerline networks to improve reliability.