A three sided die made of symmetric semicircular wedge-shaped "slices".
After rolling, result can be read from above (e.g. for 3, two "3"s will show on the fins).
Variants menu chooses between the following:
Medium: has holes near the top such that this can be used as a bead, necklace, etc (so you'll always have a d3 on you).
Small: SAME SIZE but without the holes or loop.
An alternate version with concave numbers (and a few other changes) can be found here.