Plastic Threaded Drain Through-Hull Fitting (27, 30, 33 mm)

This plastic threaded through-hull drain is a critical component for keeping your boat dry and well-maintained. Mounted typically on the transom (rear) or low on the hull, it allows you to easily drain out any water that accumulates inside the boat. The fitting is made of marine-grade plastic that resists UV rays and corrosion, ensuring it can withstand harsh sun and saltwater environments without cracking or degrading. With an internal thread design, it accepts a screw-in drain plug that you can tighten securely to prevent water ingress, and remove whenever you need to let water out.

Versatile sizing: Available in three sizes – 27 mm, 30 mm, and 33 mm – this through-hull can accommodate different drainage capacities and boat sizes. Choosing the correct size ensures optimal draining speed and compatibility with standard drain plugs. Each size features the same reliable build quality, differing only in diameter to suit various requirements.

• 27 mm size: Smallest option, suitable for compact boats (e.g. dinghies, small fishing boats up to ~5 m) where a smaller drain opening is sufficient for the lower volume of water. Ideal for draining minor rainwater or splash water when the boat is on a trailer.
• 30 mm size: Medium option, great for mid-sized boats (~5–7 m). Provides a faster drain rate for vessels that may ship more water or have larger bilge areas. A balanced choice for general recreational boats.
• 33 mm size: Largest variant, recommended for larger boats (around 7 m and above, or those carrying more gear) that may accumulate more water. The wider opening allows quick evacuation of water, which is important for safety in rougher conditions or heavier loads.

Installation of this through-hull drain is straightforward: drill the appropriate size hole in the hull/transom, insert the fitting and secure it with the included back nut. Apply a marine-grade sealant under the flange to ensure a watertight seal. Once installed, you'll have a convenient drain point – simply unscrew the plug (not included) after each outing or whenever you need to empty water from the hull. By regularly draining out water, you reduce moisture-related damage and keep your boat lighter and safer.