Find your perfect Pandora ring size and avoid the hassle of exchanges. This easy to use ring sizer works like a belt. Simply push the end through the fastener to form a ring shape, and slide it onto the finger you wish to measure. Make sure it is a comfortable fit, and that you can slip it on and off your finger. The curved edge of the fastener will point to the size that will best suit your finger. This ring sizer is made from durable silicon, and comes with an instruction booklet to help you find your perfect size. For ring stacking and rings with a wider shank, consider selecting one size bigger for the most comfortable fit.when selecting a ring with an open shank, consider selecting one size smaller for a tighter fit.