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Unfortunately even though these the polypropylene fittings look the same, they are assembled differently than the acetal fittings. As can be seen in the picture bellow the old acetal fittings consisted of one solid main body. But the new polypropylene fittings consist of a two piece body.
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We currently submerge one side of the fitting polyproplyene fittings in water, and intern, water has been flowing between the body pieces which is not sealed or reinforced with an o-ring.
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