Topnisus [Pack of 10] Clip-on Ferrite Core Ring Bead Anti-interference High-frequency Filter RFI EMI Noise Suppressor Cable Clip (7mm inner diameter) Package included 10pcs ferrite core Usage- anti interference, improve signal and filter Easy to install with double snap clips Clip on all kinds of cables, like USB cable, Date line, AV cable, Phone, Power cord, Coaxial, Audio, Video cables etc., Color : Black; Material : Plastic(Housing), Ferrite(Core)