For use on fish. meat and fruit: while Boning Knives or Cleavers are more suitable for coarser tasks. especially for meat. The WÜSTHOF Classic 6" Flexible Fish Fillet Knife with its flexible blade. is particularly suitable for wafer-thin filleting. Precision cutting of meat. loosening the fish fillet from the skin or peeling fruit – these are the Fish Filleting Knife's special talents.