This worm hook with a screw keeper was supervised by tester Mori Kohei, also known as "Morizo," a chinning evangelist who calls the Yodo River in Osaka home. When chinning, which often involves long-distance casting and searching the bottom, slippage of the worm due to snags or missed bites can lead to missed opportunities and fatal poor handling. The screw keeper securely holds the worm in place, reducing slippage and increasing the chances of encountering a fish, while the hook, designed specifically for chinning, will catch the target's jaw.