〡Radio Noise Filter Ground Loop Isolator Connectors 3.5mm/0.1in Car Stereo

Durable and Wearable: The ground loop Isolator is made of plastic material, which is light weight, wearable and durable. Main Function: The ground loop Isolator can eliminate the noise generated by the car voice frequency subwoofer, improve the sound quality, and produce better sound effects.

eBay