AUDIOVOX isolation transformer

I found this device in a packet that came with our trailer, I'm not exactly sure what it does.
Anyone on here know what it's for? My search on the internet indicates that it my be for a radio.
I'm assuming it goes on my Concertone sound output jacks.

Check this out:

http://www.discountmobilevideo.com/items/item389.htm

TC

So that is what you would use when U plug a DVD player in the plate on the wall maybe.

So, it's a noise filter. Thanks



Audiovox IST2 Isolation Transformer: wide range isolation transformer used with FM modulators to help reduce noise from DVD players, VCP players, etc.