https://tsefknife.com/product/sakai-kikumori-shirogami-2-kasumi-unagisaki-edosaki/
Sakai Kikumori Shirogami #2 Kasumi Unagisaki Edosaki – TSEF KNIFE
An unagisaki is a specialized knife for filleting eel. The sharp tip is used to pierce the eel near the head, then slid along its body to open it up.
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