4PCS Brass 1/2 Inch NPT Caps Outer Hex 1/2" NPT Female Thread Socket Pipe End...

【Hex Nut Design】Hex nut for easy tightening and loosening. Easy to use. 【Solid Sealing】Designed to create a tighter seal. Thread plug are also great for blocking off intake manifold water ports, water pump ports, water temp and oil sender holes, engine block holes, etc.

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