The LintAlert is a smart, easy-to-install home safety device that monitors and displays the back pressure levels found in the exhaust conduit of the dryer. Pressure levels found in the duct work between the back of the dryer and the exterior vent hood typically increase over time due to lint build-up or other restrictions like birds nest or vent hoods that become inoperable. City Duct Cleaning, Inc. now carries the LintAlert.