Similar to Premier, but black and white rather than the original brown tones. 57 × 30 mm. Harmony is in the hardest Fo-Mac group. Compression-molded Fo-Mac formulas differ from modern urethane and differ from one another. Sure-Grip says floor material, skater weight, temperature and other conditions affect performance. Fo-Mac products should not be assigned an invented urethane A durometer. The current manufacturer page does not specify the sold pack quantity. Confirm quantity with Diamond before ordering. Photos show an example variant. Select your size or color where offered; confirm stock with Diamond.