Lead is fundamental in all fishing techniques: without the possibility of ballasting the primers, surface techniques would be practicable almost exclusively (especially at sea, where the current to be countered is strong) and launches would not be possible. The plumbing allows both to reach fishing areas away from the fisherman, and to place their pitfalls in the established layers of water. It is essential to make a correct calculation of the weight and distribution of fishing lead on the frame used.