EMI Power Line Filter (4-Pack) - Reduce Electrical Noise for Home Theater, Audio Systems & Office Electronics

These filters work. All you need to know is the electrical circuit grid in your walls and have a meter to measure. VERY valuable and effective product! Remember, especially in Apartment buildings, dirty electricity in walls tends to be very high, as you're sharing walls with neighbors that are double-wired. I have 14 filters in a small one bedroom apartment in LA. It took that many to get the fields down, but THEY WORK! Fields piggy back onto each other as well. Dirty electricity is the easiest, and relatively cheapest field to "control" of the 4. Unfortunately in apartment buildings in big metropolitan areas you're pretty much screwed for RF wifi. Steterizers can't help you there, but then again they do because they cut down the overall EMF level.