Plastic elbow box is designed to connect the copper elbow using a mechanical coupling so that it is fixed without any heat source but by tightening the nut. It is the perfect solution for connecting copper fittings to PEX pipes. It is manufactured with an internal attachment and has an internal hole for the elbow to be fixed by means of a nut. Made of high quality materials, suitable for water systems, central heating and floor heating systems, and comes with brass nuts.