Gold plated stroboscope disc for turntables. The disc is made of glass fiber, and markings are made of gold plated copper. It is manufactured using PCB (Printed Circuit Board) fabrication process, and the plating is technically called Electroless nickel immersion gold (ENIG).
Unlike ordinary printed discs, the markings are super sharp and extremely precise - against the black disc resulting high-contrast image to check the rotational speed quickly. The disc has a diameter of 98mm (3.86 inches) to fit within the record label, so you can check the speed while you are actually playing the record (most turntables slow down a bit when the needle is on the record).
The disc is double sided; one side can be used with 60 Hz lamps, while the other side is to be used with 50 Hz lamps.
The LED strobe light shown in the video is soon to be available - stay tuned!