When you buy electronics product direct from china , you should know chinese electricity. 

China uses 220-volt electricity, although some five star hotels are wired for 110-volt electricity. In general, you will need a power converter for 110-volt appliances (most US appliances).

A decent quality converter can cost anywhere from US$20 to US$50. It is a good idea to come prepared with one, as most stores and even supermarkets in China do not carry them.

You may also need an adapter plug to use your electrical appliances. China uses the following two types of plugs:

Machines designed for travel, such as laptops, usually don’t require a converter, but may need an adapter plug. Be careful with other appliances, such as phones, hairdryers and clocks, which are common travel items but may not be designed to operate at 220-volts. Electrical appliances purchased in continetal Europe will usually work fine.