Replaces a 4-sided die (d4)Trade that sharp pyramidal floor caltrop for a nice smooth ring!Our rings are wider than most so be sure to use a WIDE-BAND finger guage when getting your fingers sized! You may even want to consider getting a HALF-SIZE LARGER.Ring Sizes Ring WidthSizes 5 to 8.5 6mmSizes 9 to 12.5 8mmSizes 13 to 16 10mm