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Larsen
Water heater connector. Stainless steel. 3/4"x18" female x female pipe thread. Very flexible.
Genova Products Insert Fittings Steel Insert Coupling
Tigre USA Reducing Male Adapter (Reducing Mipt x Insert)
Tigre USA Reducing Male Adapter (MIPT x Reducing Insert)
Master Plumber 1/3-HP Sump Pump Zinc & Plastic
Fernco Proflex Shielded Specialty Coupling