This is a 7/8" Round Glass Jewel Reflector in 6 colors: Your Choice of Amber, Blue, Green, Red, Clear, and Clear Rainbow (Polarized).. These were used on Schwinn balloon tire 9 and 6 Hole Racks and Other Vintage Bicycle Racks. Also used on Antique Automobile and Motorcycle Licence plates. The reflector has a #10 threaded mount stud, that is 5/8" long, comes with a nut, and mounts to a 3/16" hole. The photos were taken with the reflectors reflecting Light, you can see the color and brilliance, when not in direct light the reflectors are a deeper Antique Color. A Beautiful Glass Reflector to accent your Antique Schwinn Bicycle and Other Vintage Cruiser Bikes.