17.4mm inner diameter. (7-7 1/4 US/Canada ring size)
Smash is my first shapeways submission. I'm currently waiting for my silver print on order. More pictures to come. The wood inlay isn't included if ordering from here, but it's a simple DIY if you have some 0.5mm veneer lying around. Really, you could personalize the inlay with anything. Print a pattern on some Acetate and lay it in there. The possibilities are endless!