Check the listing for details. Car Stereo Radio Audio Amp Deck RCA Ground Loop Isolator Noise Filter Suppressor. Condition: New. Listed at 16.89 USD. The Music MastersDiscount Electronics & MORE! You are looking at... Item: Car Stereo Radio Audio Amp Deck RCA Ground Loop Isolator Noise Filter Suppressor Condition: New Factory Specifications: Normal 0 false false false MicrosoftInternetExplorer4 Comments: This is an effective way of reducing engine noise in your sound system that often comes from a ground loop. It's excellent at reducing "alternator whine". This is the noise that you hear that varies up and down when stepping on the gas. It's commonly used with systems using amps to filter audio signals and match the impedance between components. It connects with RCA plugs in-line between your amplifier and radio. We find it usually works best on the amplifier side. Keep in mind that "engine noise" can come from a number of sources and is directly relative to the quality of the overall installation and the equipment used. This is often a low-cost solution that overcomes many of those problems. This can be an easy fix and always worth a try since it's just plug and play. We are always happy to take it back if it doesn't work for you and we will even pay for return shipping so you have nothing to lose! We like to use these with every system as it just makes for a more detailed and refined installation. Even if you don't have noise you can feel good that your components are working with a clean filtered audio signal. For the quality and price with our fast and free shipping you simply can't go wrong. Look in our store for more deals on all types of car audio equipment. Radios, amps, speakers, etc. We stock a great selection of quality consumer electronic items, parts, accessories, and more! You won't be disappointed! Thanks for checking out one of our items! Please take the time to look at everything we have up for sale and check back often. You never know what you will find. We have been in business for over 30 years! We can best be described as an "old school" stereo shop and electronics store with a modern twist. Quite simply, we know what we're talking about, always guarantee your satisfaction, and promptly take care of our customers. Shipping & Handling for this item is FREE everywhere in the United States. For international not listed, contact us for approval and a shipping quote before making your purchase. Thanks again for looking and as always your business is appreciated!