> If you are concerned about strength, you might want to consider GRADE 8
> bolts, which are much stronger than the 'normal' grade 5.
> Both ACE and HD have these in stock. . . .
However Grade 8 doesn't have the same properties as Grade 5, it is much more
brittle for example. I've used stainless with no noticeable trouble, and
I've used galvanized (though they were longer since getting the exact length
is a challenge) but it would be wiser to stick with what the engineers
designed for the product.
The hardware is available direct from Radian/Rohn or suppliers such as
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