This collection of rings is ready for 3D printing.Ring sizes 15.5 16 16.5 17 17.5 18 18.5 19 19.5 20 mm. Approximate weight of rings by size(GOLD 14K): 15.5mm-3.4g 16mm-3.5g 16.5mm-3.59g 17mm-3.69g 17.5mm-3.79g 18mm-3.88g 18.5mm-4.02g 19mm-4.12g 19.5mm-4.21g 20mm-4.31g. Width - 4 mm. Thickness - 1.5mm. I can make to order with your parameters.