Good value for quickly figuring out the sizes of rings and fingers . Essential tools kit for professional and beginner, designed for wire working,craft wire, wire wrapping and wire jewelry, easy to use . The Ring Mandrel is made of aluminium material, US UK standard, easy to read size chart on mandrel for full and half sizes 27 Pieces Ring Sizer Set made of steel,US size(0-13),come in half sizes, come with a flexible cable with a screw connection which can be opened easily . The soft rubber hammer has two sides, can be used to flatten or strengthen wires, rubber head would not leave traces on the jewelry or damage your jewelry . Heavy-duty mandrel equiped with hammer, will make your rings round again easily. Do wire wrap rings and this is perfect for the construction of the ring. Holds shape perfectly and easy to maneuver .