DESCRIZIONE
The device has a buoy (10) connected in a reversible manner to an immersible support by an ejector type electromagnet (25) and a polar plate (14) that are respectively integrated to the buoy and the support. Pulse or programmable type deactivation units deactivate the electromagnet, and the support is integrated to an immersible object i.e. fishing pot. Automatic return type protection units constituted by traps (15, 30) protect the electromagnet and the polar plate when the buoy is taken away from the support. The electromagnet and the polar plate are made of stainless steel.