I am not going to bother rewriting what I assume is Chinglish (Chinese and English), this gadget is relatively self explanatory. It is an iPhone/iPod sync cable that has the ability to switch to charging only. Still interested, yours for $12.99 here.
If you are at home, you naturally will sync (and also charge your iPod / iPhone with your PC, however, if were out or at your office, you may just want to charge your iPhone / iPod, if you plug your iPhone / iPod with other computer, of course, it has no problems, just that it may have some little disturbances to you.
Here we have this cable for you to manage your iPhone / iPod. This cable is designed to have 1 button on the Dock connector, one side is at any other ordinary Dock cable for iPhone / iPod. To hotsync with and charge your iPhone / iPod; if you just want to charge your iPhone / iPod, you may push the button to another side, then no matter which PC / laptop that you connected with, it will just drag power from the computer to charge your iPhone / iPod, will not hotsync with.