iTrip is a large family of products with a distinguished heritage. All iTrips send your music wirelessly to your FM radio so you can listen through your own speakers.
This particular one is called “auto” because it gets its power from your vehicle’s 12 volt accessory outlet or cigarette lighter. It's called “universal” because it works with almost any portable audio device that has a standard 1/8” headphone jack.
And the “Plus” in the name of this iTrip model refers to its ability to charge a portable player by means of a built-in USB port. (Check your player's documentation for charging capability.)
Plug in your player’s USB charging cable. Not only do you get to listen to your tunes while you’re traveling, you arrive with a fully-charged player.
Technical Specifications

• Play and charge your MP3 player on FM radio.
• Antenna: Built-in.
• SmartScan Technology.
• Power: Provided by cigarette lighter or 12 volt power outlet (no batteries required)
• Modulation: FM stereo.
• Frequencies: 87.6 – 107.9 MHz.
• Oscillator: High stability crystal, phase-lock loop control.
• Frequency Response: 50 Hz to 15 kHz.
• Dimensions: 12.5 mm x 26 mm x 72 mm; total length including cable: 85 cm.
• Instruction Guide.
• Manufacturers Guarantee.