Joiner / Reducer to connect 25mm Blue MDPE Water Main Pipe to 15mm Copper / PEX / PB Pipe. The light grey side is for the blue MDPE pipe and the brown side is for Copper/PEX/PB pipe. A simple Youtube search for "plasson plassone plastic plumbing fittings" will bring up an instructional video with examples of all pipe type connections for these fittings.
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