This sterling silver box chain is threaded with 18 beads measuring 4mm each. They are held in place by tiny cups, so they do not travel around the length of the bracelet. Both ends of the box chain are threaded through a larger 7mm bead and each end in another 4mm bead. This larger bead is used to adjust the size for an exact fit, meaning that, because it is 10 inches long, it can be worn on the wrist at adjustable lengths.