The ADS 1565AA is a split coupling which is 10.4" wide and is used for 15" pipes. This coupling is NOT to be used for culverts larger than 15" in diameter. It is made of High-density polyethylene (HDPE), a type of plastic known for its strength, malleability, and for being light-weight and FDA-approved. Please note that this product does not include a gasket. This non-pressurized split coupling is a genuine part manufactured by (ADS) Advanced Drainage Systems.