Legacy Noise Suppressor - Rated 12 Amps Power and Reduces or Eliminates Engine Interference - Compatible with Receiver, Equalizers and Amplifiers for Car Stereos - LN71 ELIMINATE ENGINE INTERFERENCE: This noise suppressor eliminates annoying engine interference and hum that. Most noise on a car happens when the vehicle alternator puts too much electricity and this solves that FULL FREQUENCY RESPONSE: car stereo to produces powerful resonance and while filterinh the electrical interference coming from the speaker EASY INSTALLATION: Attach the red wire to 12v on the fuse box or battery then attach the blue wire to the power cord of the radio where the electricity is going. Lastly, ground the black wire to the vehicles frame or any available ground wire 12 AMPS POWER: A noise suppressor that is rated with 12 Amps power for an excellent performance. It is compatible to receivers, equalizers and amplifiers for car stereos 1 YEAR WARRANTY: We guarantee this noise suppressor with both a 30 day no hassle money back return policy and a 1 year manufacturers guarantee