This twenty sided die is numbered for use in tabletop and roleplaying games with numbers on opposing sides always summing to 21. It is designed to be balanced and give a fair result. (A version of this design with numbers arranged in a spindown pattern, for use as a life counter in trading card games such as Magic: the Gathering is also available in my shop.)
The faces of this d20 are shaped from spiraling ribbons of steel that encircle the numbers. This design is quite a bit larger than ea regular spindown d20, and it measures about 32 mm across its opposing faces.