EasyPro Pond Products Pro-Series Inward Curving Extension Module, 16" This item is the curved piece in the middle of the picture. These cannot be used alone and must be purchased with ends EWS18, EWS34, or EWS50 Straight spillways of 18", 34" and 50" come assembled, curved spillways and spillways over 50" come unassembled due to shipping constraints. The straight, inward and outward pieces are interchangeable and can be used in any combination Dual bulkheads (included) allow incoming water from either or both ends. A plug is included for whichever end is not used Use inward curving pieces to create a concave waterfall, use outward curving sections to create a "peninsula" with water falling off three sides or use the inward and outward combined together to create an "S" shaped waterfall! Easy bolt together assembly - no drilling needed!