Smaller shaft anodes as above
with two clamping bolts
are available in sizes from 1/2"
to 1 1/4" and for 20 and 25mm

Larger anodes have four bolts.
Sizes 1 1/4" to 5" and
also 30, 35, 40, 45, 50, 60, 75mm.
See also collar anodes
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