Water flows around nose of solid gutter cover and into gutter through slotted channel. Helps keep leaves, pine needles, and other debris out of the gutter. 4 ft sections install in 4 in , 5 in , and 6 in metal gutters. Slides under shingles and hooks to the front edge of the gutter. No special tools required. Flex design accommodates many different pitched roofs. Made of rigid PVC.