Used for water supply networks with a nominal pressure of 10 bar (calculated for 20°C temperature), installed buried in the ground. Manufacturing method by mechanical processing on machines for PE100 electrofusion couplings, with the electrofusion fitting resistance embedded in material with dimensions corresponding to SDR 17 (ISO S8), according to EN 12201-3:2011+A1:2012 and EN 1555-3:2010+A1:2012. The active clamping system is ensured by pipe-in-pipe manufacturing technology. This way, no auxiliary devices are required for installation. Welding voltage 40 V. 4 mm connectors. Welding is performed by authorized welders with appropriate equipment and in compliance with the welding procedure. Welding is performed in two separate welding zones, which are also welded in a single welding sequence without preheating, one for each end of the coupling.