The ST superstructure is a structural extension for Try tanks (without cover) by Euro-Plast. The extension pipe allows the tank to be placed deeper in the ground. This increases the possibilities when assembling the set.
Like the three-layer tanks, the ST extension also features a structured wall. The tank extension is made of high-density HDPE polyethylene. This is a highly durable material that is resistant to mechanical damage and adverse external conditions. It is also not affected by chemicals, including corrosive wastewater. This makes the product very durable and works without breakdown for many years. Its durability is further enhanced by the multi-layer wall.