Plain engagement rings have always been popular, and there are roughly 5 basic diamond-less ring profiles you can choose from. Traditional Court This has a curve both on the outside and the inside, aimed at facilitating a comfortable fit. The curve is minimally rounded for a soft feel. It is meant to match the standard engagement ring band. D Shaped Ring This particular style gives the most rounded shape on the outside, which looks like the letter “D”. The inside stays flat. Flat Profile The cross-section of this style is rectangular. With flat outer and inner surfaces, this shape is highly squared and has a sharper edge than the two profiles mentioned above.       Flat Court This style brings together the features of the flat profile and the traditional court. The outer surface stays fully flat, while the inside feels more rounded against the finger. Concave The outer edges of this style are more prominent than the center, giving it a concave look that is the opposite of the D shape. It is very hard to resize a ring in this style.