Stroboscope, A hardboard disc of 255mm diameter., Each

Details

Here is the corrected text: This stroboscope features a 9.5-inch diameter rotating disc on its handle, which has a total height of 18 inches. The sturdy plastic disc has slots and includes a finger hold for comfortable grip. The handle is equipped with a rubber grip, making it easy to use and ideal for studying periodic motion and speed of rotation.