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Thru Hull Step Wrench


Model # 6607741 | Mfg # THT-530
In stock online.
THT-530 makes the installation of standard GROCO thru-hull fittings possible 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 monofilament through the locknut or seacock. With the fitting pulled firmly against the hull, the locknut or the seacock may be screwed onto the fitting.Designed for Groco Thru Hull fittings from 1/2 inch up to 3 inches. This tool may not be compatible with fittings from other sources.

Thru Hull Step Wrench

Type Tools

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by PowerReviews
Groco Thru Hull Step Wrench

(based on 1 review)

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Reviewed by 1 customer

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Completely Useless

By Captain Conrad

from Easton, CT



    • did not fit
    • Useless

    Best Uses

    • Paperweight

    Comments about Groco Thru Hull Step Wrench:

    I had three thru hulls to remove on my boat, to me relocated. I bought this tool against the advice of a West Marine in-store adviser. He was completely right. It was useless. It did not fit any of my thru hulls. I managed to remove my three through hulls using a pipe wrench, a hammer and a grinder.

    AVOID AVOID AVOID. USELESS TOOL. Does not mate up to any of my thru hulls. With seven steps you would think it would but it doesn't. Save your money. I am fighting with Groco on returning this.

    • Was this a gift?:
    • No

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