My Friend Spooner (3/4)

I saw a kit at Barnes and Noble that was geared toward little kids. However, it's something that every law enforcement officer has access to.

Well, I spoonerized the two-word title. (That is, I switched the first consonant sound of the first word with the first consonant sound of the second word. Usually, this alters the spelling; in this case it didn't.) What remained is a two-word phrase which means "GREEN CRUSTACEAN."

What are the old and new phrases?


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