B-Line Eaton series runway dropout kit, Used to provide a smooth radius for cable exit, Cable tie down holes provided, 20" steel runway drop-out, 18 g

A drop-out gives the cable a smooth radius where it leaves the runway and turns down to a rack or cabinet. Running copper or fiber over a bare stringer edge puts a sharp bend and a metal edge against the jacket. The SB2129U20FB is a formed steel piece that supports that turn, and it has cable tie down holes so the bundle can be dressed and strain-relieved right at the exit point.

It measures 18 inches wide, 4 inches high, and 4 inches in length/depth, and weighs 3 lb. Light enough for one person to hold in place while the mounting hardware is started, and the 4 inch projection is what you need to clear when planning the drop point under the runway.

It is A569 steel, 18 gauge, with a flat black powder coat, so it matches standard black-finish B-Line cable runway used in most telecom rooms. Powder coated steel rather than plated, so it is an indoor finish, not a corrosive or wet-location part.

It ships as a kit, and the part itself is the formed steel drop-out with cable tie down holes. It does not include the ladder rack, the wall angle, or the cable ties you will use to dress the bundle, so order those separately with the rest of the runway build.