וְכ֤וֹבַע נְחֹ֙שֶׁת֙ עַל־רֹאשׁ֔וֹ וְשִׁרְי֥וֹן קַשְׂקַשִּׂ֖ים ה֣וּא לָב֑וּשׁ וּמִשְׁקַל֙ הַשִּׁרְי֔וֹן חֲמֵשֶׁת־אֲלָפִ֥ים שְׁקָלִ֖ים נְחֹֽשֶֽׁת׃
他頭戴銅盔，身穿鱗甲，鎧甲重五千舍客勒銅。
Sifra
5) ("fins and scales") This tells me only of (fish with) an abundance of scales and fins, such as kiponoth. Whence do I derive the same for a fish that has only one fin and one scale? From (Vayikra 11:10) "All that do not have (lit.) a fin and a scale (kaskas)." R. Yehudah says: two scales. And even though there is no proof for this, there is an "intimation" for it, viz. (I Samuel 17:5): "and in armor of scales (kaskasim, plural) was he clothed." R. Yossi b. Dormaskita says: The leviathan is a clean fish, as it is written (Iyyov 41:7): "Its (the leviathan's) pride is the strength of shields" — these are its scales; (Iyyov 41:22): "Beneath it are sharp shards" — these are its fins.