The Amerimax gutter and downspout system features a black baked on factory finish paint and durable aluminum construction. Our gutter systems will help control roof run off and help prevent erosion. The inside box miter is used to connect two pieces of gutter turning an inside corner of your roof line to allow free flow of the roof drainage to the downspout. It is connected to the gutter length with 2 Seamers connectors (not included). Sealant is required for installation (not included).