This is a tool to set the 14mm rivoli into settings! No more setting each prong by hand. This tool will set all four at the same time. Save up to 2/3's of the time setting stones. All prongs are set perfectly even with this tool! Smart Setter Stone Setting Tools - Easy to use tools to set your stones into a bezel cup or cup chain with one push. Select the appropriate size tool for the stone you are using, place your stone in the cup, then press straight down with the tool. Sizes are printed on the handle for easy reference. Curved wooden handles sit comfortably in your hand.