Free 

I designed these to solve grip problems for hand dexterity and nerve damage. It allows a person with limited feeling or dexterity to pull cords/ties. Designed for tightening a transparent cover for a gazebo, it should be usable in any cover/tent scenario. It provides maximum leverage with minimal dexterity (essentially an unbent finger). Also included is the complementary hook for mounting on posts, etc., allowing for easier tie-down and release.
Tested using Hyper PETG and PLA.
Added a second stronger hook design.
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