Rainchains - Medium Weathered Steel Square Cups - 3121-M-CORTA new square cup in a medium size, made of a special steel that is meant to rust, but only on the surface. Similar to COR TEN steel. These cups are very strong and no welding is required to make them. Large nuts and thick wires complete this robust product. Will handle all rainfall conditions. Features: High Quality Materials, this chain will last for many years! Works well in heavy rain Includes a Gutter V hook for easy installation Made in the USA