Unit Definition (firkin [butter, soap]) The firkin [butter, soap] is a traditional unit of weight for butter and soap, equal to 4 stone or 56 pounds (about 25.40 kilograms).
Unit Definition (kwan [Japan]) The kwan is a traditional Japanese unit of weight equal to 6.25 kin, which is about 8.27 pounds or 3.75 kilograms.
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