1in MPT Pipe Plug w/ Internal Allen

The 1 inch MPT pipe plug with internal Allen from FRAGOLA is an essential component for any serious engine builder, custom fabricator, or mechanic working with hydraulic and pneumatic systems. This hex-socket pipe plug seals off unused 1-inch male pipe thread ports on adapters, manifolds, and custom fuel or coolant lines, eliminating the need for temporary caps or tape wrapping that can leak under pressure.

FRAGOLA's design features an internal hex-drive socket that allows tool-free or wrench-assisted installation and removal, which is critical when space is tight and conventional flat-head plugs are inaccessible. The 1-inch MPT (male pipe thread) connection ensures a tight, tapered fit that prevents weeping under engine heat and vibration cycles. Constructed from durable materials rated for standard automotive coolant, fuel, and light hydraulic service, this plug handles typical underhood temperatures and pressures without degradation.

This plug is ideal for engine builders, hot rodders, and mechanics fabricating custom fuel distribution blocks, intake manifold adapters, or hydraulic-assist systems. Its design allows it to fit neatly into tight engine bay environments where larger plugs would interfere with hoses, belts, or adjacent fittings, making it a versatile choice for various applications.