Gutters act as a part of a rainwater drainage management system. Uncontrolled rainwater from the roof can damage your foundation, cause siding and wood rot and encourage interior mold and mildew. End caps close and finish the ends of the gutter for proper function of the rainwater management system. Fits our 5 in. gutter. - Amerimax Aluminum Right End Cap for 5 in. Gutter, White