How many times have you wanted to charge your iPod or iPhone from your computer or some else"s, without the hassle of synchronizing to iTunes, or worse, worrying about accidentally erasing all your music?Introducing the Tune Blocker. With the flip of a switch, Tune Blocker allows you to choose whether you want to simply charge your iPod or iPhone, or sync it to your iTunes library as well.On "Charge Only" Setting: plug & unplug at will no more warning messages safely charge from any computer protects your music from being overwritten On "Sync & Charge" Setting:sync & charge — just like a regular cable