Channel tray - Small (4" or 6" wide) for small quantities of cables or instrument tubing. NEC Article 376 covers metal wireways. Key differences: This is where. If you're working on an electrical project, you've likely asked yourself this: Should I use a cable duct or a cable tray? It's a common question. People worry about which system is safer, more cost-effective, and easier to install. However, they are not interchangeable. We distinguish different tray constructions: solid, perforated, mesh, ladder, comb, and flexible—each has different practical applications. Trays are used in both. Cable duct vs cable tray: trays offer less protection and require fire-resistant cables for exposure to environmental hazards.