Interlock is not a single ring, but three rings that are bound together like a chain.  They are worn as one ring with each passing over the top of the other two. The rings can have contrasting finishes like the polished, angled brush, and beadblast  ones shown. To wear it, you hold the two outside rings and twist one way or the other to arrange it like the secondary picture, where the middle ring is flat with the others, and when you slip your finger in the center, it rolls right onto your finger with a unique braidlike motion.  This prevents the rings from stacking wrong and feeling tight.  The ring shown has 3mm width links.