It has a scaly, oval body with a striking dark blue-coloured back and a white belly. The average size is around 75 cm, and around 10 Kg in weight. It is a migratory species and in the summer months it goes to the Cantabrian Sea in large groups, where it is caught by rod and reel in the months of July and August to be canned at the just the right moment as regards fats and texture. Immediately after it is caught it is transported to the factory fresh, to be cut up, boiled and packed in the different canned specialities.