I m using this since long and i bough this for $37.. Really it Eliminate humming noise in your car with the integrated High Performance Audio Noise filter.. Feels like seating in a home theater without unwanted noises.
Yes, like a home theater. The filter is magic. Seriously though, open up the filter. The wire just loops once around a magnet. It works, but you could literally make one of these using a fridge magnet and tape. You can buy these filters on monoprice for less than a dollar.
I don't even buy stuff, I just come here for the comments.