Brass Sump Plug Adapter Male 1/4"x28 UNF to 3/8"BSPT Female Thread for Sensor/Gauge. This high-qualitybrass sump plug adapter is designed to convert a1/4"x28 UNF male thread to an3/8"BSPT female thread, making it ideal for connecting sensors, gauges, or other fittings.
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