One piece waterfall spillways ideal for creating pondless style water features. Roto-molded for excellent strength. Dual inlets — 2" spinwelds (pre-installed) allow for easy plumbing into either end, a plug for unused end is included, CF12E has one 11 /2" inlet pre-installed. 4" diffuser tube lays across the bottom of the spillway between inlet fittings. Water enters from either end (or both ends) and spreads out evenly across width of spillway. Gravel can be used to fill the inside of the spillway creating a natural, even looking waterfall.