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What this video covers

High-quality silicon bronze through-hulls, such as those manufactured by GroKo, do not require electrical bonding because the attached hoses provide sufficient isolation.0:35 Bonding these fittings to a zinc or aluminum anode system often accelerates anode erosion without providing a benefit.0:58 Conversely, through-hulls made from DZR (de-zincification resistant) brass or other inferior brass alloys require bonding to mitigate corrosion.1:22 These brass fittings are prone to de-zincification, a process that leaves the metal porous and brittle, leading to structural failure in as little as two years.2:08 Visual inspection may not reveal internal degradation, but brittle fittings can snap under minimal physical force.2:56 To avoid these risks, replacing questionable metal through-hulls with high-quality plastic fittings, such as those from True Design, offers a durable alternative that meets rigorous ABYC physical load standards.3:00 Proper material selection remains the most effective defense against through-hull failure.4:15

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