The GRAM-BOX ballast system for mounting solar panels is an innovative solution designed for use on flat surfaces and pitched roofs with a slope of up to 10 degrees; Main features: The tank is delivered to the user with glycol concentrate and weighs 10 kg, therefore, to determine the recommended weight of 60 kg, add 50 liters of mains water to the tank, which translates to obtaining the recommended weight and concentration of the glycol solution of 10.7% ;