Brass plugs and nipples are used to connect pipelines or devices with main pipes of the same or different diameters. As the pipes are mainly used of steel, the method of "splicing" and mutual "penetration" of the thread on the border of brass + steel materials is much lower than in the embodiments of cast iron + steel or steel + steel materials - so you will be able to disassemble such jointing easily in long time . This is important fact, especially for the equipment that requires periodic maintenance with disconnecting from the main system (filters, radiators, control systems, etc.).