Soft-shells are graded by size, measured across the back, tip to tip: Mediums, 3 1/2 to 4 inches; Hotels, 4 to 4 1/2 inches; Primes, 4 1/2 to 5 inches; Jumbos, 5 to 5 1/2 inches; and Whales, 5 1/2 inches or more.
Have the fishmonger clean the crabs, or do it yourself.
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