Bolted storage W-Tank is a light tank, easy to install and thanks to its corrosion-free composition. The plates of storage W-Tank are manufactured by flex molding process. The Flex Molding process is used to obtain reinforced plastic pieces with high glass fiber content, arranged in the direction of the stress, which leads to high mechanical strength. It consists of injecting a reactive polymer under pressure into the mold which contains the reinforcement in form of fibers, all of which is done in a controlled vacuum environment. This process of impregnation (Flex Molding) is used to build pieces in a closed mold, making it an ecological process by eliminating emissions and consumables.