Flowtech Thru-Hull Valve
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FORESPARFlowtech Thru-Hull Valve


In stock online.
Model # 7363302 | Mfg # 905106UPC # 28026149022
Flowtech Thru-Hull Valve




Flowtech Thru-Hull Valve

Name Value
Dimensions 3/4"
1 1/2"
Material Marelon
Type Valves

Product Overview

Reduce drag and maximize hull performance with Flowtech™ valves

Unlike conventional mushroom and flush-style thru-hull fittings which decrease hull performance due to the drag they create, Flowtech valves (when closed) eliminate protrusions and cavities that disturb the even flow of water along the hull surface. A smooth, unbroken hull surface is especially important to racing sailboats that need every edge they can get in light air.

Cruising sailboats and powerboats can also benefit from Flowtech valves, with reduced fuel consumption and shortened times to destination arrival.

Beyond reducing drag, another benefit of Flowtech valves is that they are made of Marelon®, a glass-reinforced polymer that is extremely strong and impervious to electrolysis and saltwater corrosion.

What’s in the box

Forespar’s Flowtech™ 905106 (offered here) includes the valve body, thru-hull and three sizes of hose pipe connections. 3/4", 1" and 1 1/2" hose barbs are included. 

Key Features

  • Designed to be faired flush to the hull
  • Valve design reduces drag
  • Will not catch debris
  • Marelon material is impervious to electrolysis and saltwater corrosion
  • Included fittings enable plumbing to 3/4", 1" and 1 1/2" hose


  • Hole size required: 1 7/8"dia.
  • Minimum bury (hull thickness) required: 5/8" (Can include backing plate.)

About Marelon

Marelon is a proprietary formulation of polymer composite compounds that uses composite reinforced polymer and additives to produce a superior marine-grade product.

  • For use above and below the waterline
  • Complete freedom from corrosion
  • U.L. and A.B.Y.C. approved


For detailed installation instructions, see Flowtech Valve Installation


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