The cbt is an affordable led lensed troffer with smooth, even illumination.
Columbia CBT LED Back-Lit Troffer Panel 2" x 4" , Switchable Lumens, 3500K, 0-10v Dim, 120-277V With its led energy saving technology, cbt is perfect for offices, classrooms and many other applications. Switchable lumen technology creates built-in versatility; choose between three configuration options for the right output with one easy switch..