Flat sided court (flat sided comfort fit) wedding rings are rounded on the inside and outside with flatter sides than the standard court (comfort-fit) wedding ring. This means that they also appear a bit deeper and are slightly heavier than the traditional court wedding ring.
Flat sided courts are not offered in the light (1.3mm) depth as there would not be enough metal to make the sides more defined than the traditional court. Once you've chosen a width, and between medium and heavy, you'll be taken to the product page where you can enter the finger size for a price.
