REFLECTOR AMBER ROUND 3-1/4" W/ ALUM GROMMET. The RT-90 is a high-quality, durable reflector that meets or exceeds federal and state eyeliner photometric standards. It's made from tough aluminum with a smooth finish to help prevent dirt build-up and corrosion. Its centermount design allows for easy field installation without the need to dig holes or use concrete anchors. This model comes with a mounting plate for easy installation.