This 30-day urinal screen offers superior splash control. Wave 3D's unique, two-sided design allows the screen to eliminate 99 percent of splash back on both sides. This prevents incorrect installation that can result in a mess around the urinal. Urinal screen contains billions of beneficial bacteria that consume odors so it doesn't just mask them. These amazing bacteria also help keep drains clean, clear and smelling fresh. Date reminder tabs along the bottom edges correspond 30 days from installation so it's easy to remember when to change out the screen.