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Thru-Hull 1-1/4", Mushroom Head, Threaded

Part #: Z5070
This National Pipe Straight Mechanical threaded mushroom style thru-hull is used in several locations to replace the original through hulls.

Some owners have reported this was used for the exhaust discharge on some early walk through transom boats with the 1-5/8" id hose going right over the threads and with the hose clamps in place was enough to seal the exhaust line.
Molded Marelon offers superior strength and corrosion resistance. Marelon is lightweight, corrosion and electrolysis free, ideal for thru-hull valves. Marelon is a modern material formulation of polymer composite compounds that uses resins and additives to produce an extremely strong marine-grade product that will not deteriorate like traditional bronze marine plumbing parts. All Thru-Hull Connectors must be installed with proper bedding compound. We recommend a maximum torque setting of 20 lb/ft. Ideal for above and below the waterline applications.

National Pipe Straight Mechanical (NPSM) threads used in marine fluid systems that requires thread compound or Teflon tape to seal. The female component incorporates a straight, non-tapered thread with an inverted 30° chamfer of the male connector on the seat of the female. This is a mechanical seal.
• Thread type: 1-1/4" National Pipe Straight Mechanical (NPSM)
• Outside dimension of thread: ~1-5/8"
• Outside dimension of flange: ~2-3/4"
• Overall length, of threads: ~3"

Technical Support

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