TRUCK TRAILER (2) Red MID-TURN 4" LED Light / Side Marker SAFER BRIGHTER Version Features chrome reflector inside the lens which makes this light even brighter, more visible 9-diode square LED light (very strong light). Functions as mid-turn light, or clearance, side marker light. Multi-angle surface design which makes this side marker recognizable from different angle. This is a DOT approved 4" BIG Side Marker. Let your road be safer!