SWAROVSKI ELEMENTS 4mm 5601 cube bead. These crystal beads have bevelled edges which adds to the number of sparkly facets. The hole size is approximately 0.8mm. These 4mm Swarovski crystal beads provide classical elegance to bracelet and earring designs. To give an idea of the difference between the sizes please see the additional image showing all the sizes photographed together. Crystal AB is crystal with a coating on one half that reflects light with a yellow and blue tinge, like the surface of a bubble.