The power block is a spinning wheel, controlled with hydraulics, that helps bring the net in. The interior rubber grips the net, leadline, and corks, pulling the net and fish aboard, where the deckhands separate and stack it, corks on one side and leadline on the opposite side, with the webbing between them. On the boat above, the power block is on a slider on the main boom, meaning it can be extended to the end of the boom when needed, or brought in closer as shown above. One end of the net is hanging from the power block in the photo above.