What is the general benchmark mentioned for an opening small enough for a Ringneck Snake to slip through?

Answer

If a quarter-inch pencil can pass through.

Because these snakes are small, they can enter through remarkably small openings, with a common guideline suggesting inspecting any gap through which a quarter-inch pencil could fit.

What is the general benchmark mentioned for an opening small enough for a Ringneck Snake to slip through?
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