Product Name : Ferrite Core Filter; Type : Ferrite Core Noise Suppressor External Size(Approx) : 2.8 x 1.5cm / 1.1 Inch x 0.6 Inch (L * D); Fit Cable Diameter : 5mm / 0.197 Inch Material : Plastic(Housing), Ferrite ( Core); Color : Black Net Weight : 50g/pcs Helps reduce EMI on AC power lines. Black plastic enclosed ferrite core for 5mm AC power cords. Great for cutting noise on USB, Firewire, Phone, Power Cord, Coaxial, Audio, Video etc cables. Easy Structure and convenient installtion. Just clip it on and you will get clearer signal and faster data transmission. Package Content : 12 x Ferrite Core Filters Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.