Unlike regular frying pans, why does the fish pan come in an elongated oval shape with an iron lid?

It is an oval shape rather than a round one. The body of the pan extends horizontally to both sides, and one end leads to a tapered handle for an easy grip^[1]. Including the handle, the dimensions are 33.5cm wide, 29.8cm long, and 11.4cm high, while the bottom surface is 21.5cm wide, 11.2cm long, and 4.4cm deep^[2]. This base allows an entire fish to be laid flat and grilled without having to cut it into pieces.

The lid is also designed to match its purpose. This pan includes a dedicated special iron lid^[3]. Generally, a weighted iron lid presses down on the pan without lifting, effectively preventing heat and moisture from escaping during cooking. Thanks to this, even the thick flesh of a fish can be cooked evenly through to the inside, and splattering of oil or smoke during the cooking process is also reduced.