Foil Flex Closeup
Although semi-rigid aluminum flex hose is recommended, the LintAlert does work with the old-style foil flex. When installing a LintAlert, it's a great time to switch to the more efficient hose (you'll save energy and increase the dryer's life span).
This image shows a close up of testing done to ensure that different types of hose do not negatively affect LintAlert monitoring. The LintAlert does provide accurate readings of dryer exhaust efficiency and can be installed in this type of hose just as easily as in semi-rigid exhaust hose.