The FA-Ltrap is a high temperature plastic lint trap that will catch the majority of the lint before it reaches an in-line booster fan on the way out of the building. Dryer manufacturers sometimes claim that no lint escapes the built-in lint trap, but some does and over time that lint will clog up a booster fan and reduce its operating life. An extra lint trap is particularly advisable if the length of duct between the dryer and the booster fan is less than 15 feet.
The metal lint traps get the job done, but they aren't the most attractive devices. This trap has a simple to remove, clear plastic cover that holds the filter in place. It's simple to use and looks better.