The elbows are manufactured from black high-density polyethylene PE100 compound. The PE100 compound is a homogeneous mixture of polyethylene, antioxidants, pigments, and stabilizers against UV radiation. The PE100 raw material complies with SR ISO 4427-1 and SR EN 12201-1 standards. Manufacturing: Injected fittings. Reference standard SR EN 12201-3: Plastic piping systems for water supply, connections, and pressure drainage systems – polyethylene (PE). Part 3: Fittings. For use in potable water supply networks with an operating pressure of PN 16 bar, installed underground. The service life is 50 years, corresponding to a usage temperature of 20°C and an operating pressure equal to or less than the PN for which the fitting was manufactured. Joining method – by butt fusion welding with fittings/pipes of the same SDR. – by electrofusion.