If you find Shanghai Tingen Electric Co., Ltd., on alibaba.com, their name really does speak volumes about their service - SHTE power!
Although they sent me an inverter for a good price, it blew up after only 2 weeks. After that they completely ignored me. Even though I was ready to admit that I might have used it 'incorrectly' (and you have to be careful of the small print with these Chinese companies), they completely blanked any attempt by me to engage them for a solution to the problem. 500USD just down the drain.
Also, alibaba.com were very poor to resolve the complaint I had. I had to jump through hoops to get any dialog going. Eventually, SHTE power agreed to send me a circuit diagram so that I could fix the unit myself. However, the circuit diagram was for a completely different piece of equipment. And then they just ignored me after that.
Don't buy from SH(I)TE power!