Single BSP Backnut & Washer Set (1 Nut + 1 Washer). 1 × BSP Backnut + 1 × BSP Sealing Washer. However,most fittings used across the market are BSP (British Standard Pipe) threads. BSP Backnuts & TPE Rubber Sealing Washers – 1″ / 1.25″ / 1.5″ – Multiple Options.
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