Size: M1.5 M2 M2.5 M3 M4 M5 M6 M8. 1/8" 1/4" 3/8" Male To Female Brass BSP Thread Extension Connectors Pipe Fitting. Material: Copper. Red copper is widely used in the manufacture of pins, screws, gaskets, hardware, pipe fittings, bearing retainers, etc.
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