The Special Features of Model TT-C: 1.Having carphone function, which you can talk freely while driving The Basic Features of Model TT-C: 1.Remote sending alarm to phone 2.Remote listening into the car and broadcasting into the car 3.Remote cutting off the engine by phone 4.Remote lock/unlock car door by phone 5.Having backup battery 6.Integrated unit with metal box 7.Car finding 8. Nice color box packing 9. Having vibration alarming, door opening alarming, power-off alarming, emergency help alarming. 10.As for the voice operation menu, we have versions in English, Spanish, Russian, Arabic, French language for choice. 11.Easy installation 12.12months for warranty