Abstract: In order to change defective buoys on the net line of a fishing net and to change the spacing between the buoys threaded onto the net line, it has hitherto been necessary to release the net line from the net and to re-secure it to the net after re-arranging the buoys, thus to re-tie it. This is a very time-consuming task, which can now be avoided by use of the novel buoy. This novel buoy consists of two identical portions, thus of two halves, which engage against the net line and which can be assembled together effortlessly at the desired location for the complete buoy. To connect the halves, a clamping member disposed to surround the barrel-shaped buoy in a groove can be used.