Square outlet boxes are available in sizes of 4 inches and 5 inches.

Quick explanation

In common electrical trade questions, the item “Square outlet boxes are available in sizes of 4 and ___” is treated as a multiple‑choice question where the correct completion is 5 inches. This reflects the next standard nominal size up from a 4‑inch square box in that example problem.

So, if you’re filling in the blank on that line, the intended answer is: 5 inches.

Meta description (SEO style):
Learn the correct completion for the phrase “square outlet boxes are available in sizes of 4 and …” and see which standard size is typically used to fill in the blank in trade exam contexts.

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