3 3/8" wide extruded aluminum profile, powder coated white. Easy snap-in installation, fast plug-and-play modular electrical wiring system. Thin design for zero plenum applications with minimum clearance above the ceiling. Used with Armstrong® 9/16" Suprafine®, Silhouette®, Interlude, Axiom® Perimeter, 4" TechZone®, Axiom® Direct Light Cove and Drywall kit.