All 12" Internal Width Channels Polymer Concrete Home » Products » Trench Drains » Polymer Concrete » Polymer Concrete Channels » 12" Internal Width Channels Polymer Concrete T1800-PB-13 12″ Internal Width Polymer Concrete Channel with Galvanized Steel Edge Rail T1800-PB-3 12″ Internal Width Polymer Concrete Channel with Stainless Steel Edge Rail T1800-PB-4 12″ Internal Width Polymer Concrete Channel with Ductile Iron Rail