Double Helix bracelet This piece fits nicely over a rubber or leather band of +/- 2.7 mm thickness, which you can find in most hobby or jewelry parts shops.. (select a lock of your choosing while you're at it). For example, take a look at http://www.sayila.nl/sieraden-maken/veters-koord/accessoires-sieraden-maken/diversen/koord-van-imitatie-leer-3mm-1-meter-s3058 So just to be clear: the model is the double spiral, not the black rubber band that is visible in the renderings. This bracelet is aimed at a wrist of about 60 mm diameter, but it can of course be adjusted with the correct rubber tube. (The curvature of the double helix piece fits exactly on an ellipse of 57x65 mm)
Feel free to ask for different measurements, using the co-creator settings.