68 POOLSTONESbySOFIKITIS What a Trapezoid Coping or It is a usually a small size coping or drain grate, so that it follows a curve in broken lines. It concerns the cheapest decoration solution for a curved pool. The oblique line may be cut at the factory according to the drawing, or on site by the fitter. It is proposed as a low-cost solution when having open curves with large radius.