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Celebrating over 50 years of Trusted Marine Service
Over 50 years of Trusted Marine Service

Groco THT530 Thru Hull Installation Tool , Sizes 1/2" through 3"

Original price $306.09 - Original price $306.09
Original price
$306.09
$306.09 - $306.09
Current price $306.09
Item locally warehoused

Free returns on all eligible orders

You have 30 days to request a return. All sale items are final sale.

Enables Installations GROCO thru-hull fittings by a single installer.

  • Slide the thru-hull fitting, flanged end first, over the tool. (It will stop at the proper step.) Tie a length of monofilament to the eye and place it into the already-cut hole in the hull of the boat.
  • Apply caulking to the flange of the fitting, and pull the fitting through the hole and against the hull from inside the boat.
  • Thread the mono-filament through the locknut or seacock.
  • With the fitting pulled firmly against the hull the locknut or the seacock may be screwed onto the fitting.
Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 1-3 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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