These rain gutter products have carbon,which boasts outstanding strength, at their core, . The rain gutters possess not only strength but also ductility similar to plastic materials. The products resume their original form even after a ladder was placed against them or they have been subject to strong pressure. They are extremely durable against high and low temperatures, and undergo virtually no expansion or contraction. In addition, the products are significantly lighter in weight than polyvinyl chloride products.

The Carbon series products are all "stronger than iron and lighter than aluminum." The rain gutters are made of a uniform mixture of carbon fiber and adhesive resin, through special processing.

In line with the added variety of colors of square gutters, colored cylindrical pipes of silver, white and cocoa are now available in addition to grey.