Advanced Drainage Systems is the worlds largest producer of corrugated HDPE pipe and related drainage products. ADS serves the storm and waste water industry through a global network of 56 domestic and international manufacturing plants and 27 distribution centers. In addition to its flagship N-12 pipe, the company offers a complete line of fittings and other accessories including, Nyloplast drainage structures, and various geotextiles. The 4 in. Polyethylene Corrugated-to-Clay Pipe Adapter snaps to the outside wall of a 4 in. corrugated polyethylene pipe and to the inside of a 4 in. solid wall pipe. Color: Black.