Product review (5 stars): Good preventive product.
I double them up and create a lint trap that only lets water pass.  Change every two weeks to a month deprending on how often you wash clothes.  Lint clogs occur deep in pipes requiring a plumber to "snake" it.  Average charge is about $100 bucks.  Cheaper here than at the hardware store.  Buy the steel mesh NOT the nylon.  Steel works best.