The worst company I have ever dealt with in my entire life I thought Comcast was bad or CenturyLink but Smart Start definitely out beats every company out there including the Indians customer service this company devices are defected they will give you a lockout which means you have to pay $60 they tell you that you can find an incident report and get your money back that is a lie they will not give you your money back and then on top of that they will not change your device I had two vehicles with this device and I have now one vehicle as Im writing this review because I just blew into the device it said I passed and it gave me a lockout day which means I have to go pay $60 I do not know how the other companies work for interlocks but I would not go with Smart Start