Introducing Isolation Bushings to prevent Bimetallic Corrosion
The new isolation bushing is made of black nylon and is mounted to both sides of the metal post (one per side).
The back side bushing would be held in place by the through-the-post fitting. The bushing on the inside of the post will be held in place by a dot of silicone placed by the installer.
The purpose of the bushing is to prevent dissimilar metals from touching one another. When they do, in an environment where there is an electrolyte present (like salt air), the two metals can electrochemically react to one another, causing corrosion, the most common example of which is rust, which can stain your posts.
Keeping the metals apart with this bushing can help prevent that corrosion. Drill hole size is 41/64 (21/32 is okay if a 41/64 bit can’t be located).
Drill hole size is 41/64 (21/32 is okay if a 41/64 bit can’t be located).
Order Part No. B-687-562-437
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