4" linear system with industry-best combination of optics, energy efficiency and visual continuity within entire Bionic series. Extruded aluminum housing. Choose from one of Prudential Lighting's Premium Colors with no set-up fee. See their P40 Series for the same great optics with a budget-friendly steel housing. 3x 2015 IES Progress Report award winner for Wall Wash, Wall Graze and Ceiling Wash optics.