... index 1.93 (for reflective sheeting/fabric, air filed paving marking) dimension:38~45um, 45~53um, 63~75um, 75~90um, 90 ... -index beads: refraction index 1.53~1.6 (for road marking, air filed paving marking) dimension:300~500um, 500~600um, 600~750um, 850 ...