We use an oval shape rod 1 1/4"x 11/16" made of 1/16" thick steel with a polished chrome finish. Rod supports are made of steel, chrome plated with 2 pins on the back for insertion in 32 mm system holes.
To ensure the stability of the rods, we always add a semi-fixed shelf directly above the rod. Vertical panels, if not supported properly would slightly buckle over time. This would result in extra space where the rods are. As a result, they become loose or simply drop off their supports.