Fellowes 22317 Perf-Ect Partition Additions Three-Tray Organizer, 12 1/8 x 12 3/8, Black Perf-Ect Partition Additions Triple Tray. Frees valuable desktop workspace. Universal mounting bracket fits panels 1-1/2" to 3" thick. Frees valuable desktop workspace. Universal mounting bracket fits panels 1-1/2" to 3" thick. Upscale perforated metal/wire design. Partition mount only.