Guardian Ignition Interlock is CO’s most affordable ignition interlock device. Guardian’s device is discreet and one of the easiest to use devices on the market. With over 30 years of experience, Guardian is one of the most trusted iid brands. Our location at 1822 Skyway Dr Unit O is CO certified with expert technicians for all your interlock installation and calibration needs. Guardian alcohol monitoring products include 24/7 customer support so we're always here when you need.