Fangrui Product Details Description: This Is A Ground Loop Audio Isolator, Acoustic Noise Filter, Eliminate Audio Current Sound, Former Signal Noise Reducer. Remove Hum. Eliminate The Hum Noise Caused By Ground Loops When The Audio Source And (some Car Speakers/home Audio Systems) Use The Same Power Supply, So As To Achieve Clear Music Enjoyment, And The Will Bloom From There. Pure Sound Quality. There Is No Damage Of Rock Music, A Better Experience, And Can Be Used On Mono. Easy To Use, Just Plug And Play, No Battery Required. Small And Portable, This Gadget Doesnt Take Up Much Space And Is Easy To Take Away. Works With Any Portable Device That Has Rca Audio Jacks, For Your Car Audio System/home Stereo. This Product Can Only Eliminate Noise And Current Noise Caused By Common Power And Common Ground Products, But Cannot Eliminate Noise Caused By Other Reasons, So You Need To Confirm The Source Of The Noise Yourself. Specification: Model: R2 Input Channel 2 Output Channel 2 Input Impedance 600 Output Impedance 600 Inst