Worthington Millwork window arches are not only attractive, but they are easy to work with. Our 24 inch to 48 inch Worthington arches are complete half rounds. Our 52 inch and larger Worthington window arches come as 100-degree arches. Built as true half rounds with 3 inch extensions on the bottom, allowing Worthington arches to be adjusted to height on the job site to fit any half round window (note: 10-324, 10-324-3, 10-200 & 10-200-3 which do not have the extensions). Arch shoes are an extra fee, please call if you need them.