PURPOSE: To provide a protection container sinking to a prescribed depth while protecting a fishing bait from external force and small fishes, delivering the bait from the container at the depth and directly fishing the objective fish.

CONSTITUTION: A sinker line 2 is connected to a swivel 1, passed through a sinker 3 and a metallic tube 4 and connected to a main line 5. The lower end of the main line 5 passed through a cover 6 and a container box 7 is looped to prevent the falling off of the container box 7. A joint line 9 is tied to the loop of the lower end of the main line 5, pulled out through the bottom small hole of the container box 7 and tied with a swivel 10.