Product review (1 stars): Fire Hazard
I installed the dryer vent guard a few weeks ago.  I noticed my clothes were not getting dry tonight.  I checked the external dryer vent and it was  clogged with lint.  The holes are not large enough to allow the lint to blow outside so it just keeps collecting on the bird guard. Very dangerous!  I'm glad my external vent for the dryer is not very high up on our house so it is easy to check. Removed vent guard for safety reasons.  I don't want to remove lint every week or two.