A 3/4″ NPT socket plug for closing large unused tapered pipe ports. This size is common on fuel and oil tanks, swirl pots, sumps, large cooler and filter housings and heavy adapter blocks, where a spare port would otherwise need an awkward improvised blank. The recessed hex drive gives a flush finish and lets the plug be fitted where a projecting head would foul. Note that a plug this size needs a large hex key, so check you have the correct drive before starting. Use thread sealant or PTFE tape on the taper and tighten to finger tight plus a wrench turn or two.