#   Nairn Marine Drain Plug and Housing – Boat Plumbing Fittings   400355

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    $9.14  each

            Brand: [Nairn Boat Inspection Ports & Spare Parts](https://www.rhsboating.com.au/brands-listing/nairn-boat-inspection-ports-spare-parts.html)

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    ### Nairn Drain Plug and Housing

Choose a Nairn drain fitting with a precision-fit sealing arrangement that does not require O-rings. This nylon plug uses a coarse single thread and is supplied with a plastic base and detachable stainless steel retainer.

The specified hole diameter is 18mm. Check the installation opening and surrounding mounting space against that requirement. The detachable retainer is part of this design, and replacement plug 400356 provides a code-specific option when only the plug needs replacing.

### Choosing and using this product

When comparing alternatives, use the specified material and intended application rather than assuming every marine fitting is suitable for every liquid. Keep the part reference with the plumbing records so future spares can be matched to the connection actually installed.

For a replacement, inspect the existing fitting and adjoining hose before ordering. Consider the direction of the connection as well as its size. An elbow, straight fitting or barbed tail changes the route and clearance needed even when the nominal connection size is similar.

Keep service points accessible and follow the relevant system instructions for fastening, sealing and hose support. Avoid forcing a hose or thread to compensate for an unsuitable fitting. Confirm the finished connection and normal system operation before putting the installation back into use.

Plan the connection from the system outward: identify the fluid application, mating thread or hose size, and the space available for the fitting. A nominal pipe-thread size is a separate measurement from a hose diameter, so compare the correct dimension at each connection.

Check the stated contents when putting together the plumbing run. A fitting-only listing does not necessarily include hose, clamps, seals or a mounting assembly. Lay out the required connections before installation so the finished arrangement can be checked as a whole.

### Product details

- Nylon drain plug with precision fit watertight seal, without O rings.
- Coarse single thread, detachable stainless steel retainer and plastic base.
- Hole diameter 18mm.
- Product code: 400355