Intoxalock is the no. 1 ignition interlock device brand in the U.S., and Intoxalock Ignition Interlock in Clarksville, TN is here to help you get back on the road after a DUI. Intoxalock has more locations than any other provider, and we can find an interlock installation location near you. We will help you understand TN interlock, or IID, laws and regulations. Our interlock installation locations are staffed with certified professionals who will install and service your car breathalyzers. For 30 years, Intoxalock has been a trusted interlock ignition device provider. Call now to talk to a TN expert.