Copper crimp rings ensure full 360 compression of the pipe over the barbs of the fitting without the risk of expansion or corrosion. crimp rings for 1/2 in. PEX, 3/4 in. for 3/4 in. and so on. A PEX crimp ring is installed by positioning it over the pipe and fittings and compressing it with the help of a PEX crimp (crimping) tool.
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